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GPGOL causes Outlook to crash
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Description

GPGOL causes Outlook to crash, even when no encryption/decryption action is taken.
The 7z file appended contains the gpgol logfile as well as the corresponding
Windows Event Log entries (evtx and txt format).

Details

Version
1.3.0

Event Timeline

Hi,
sorry for the late reply. Missed this report.

In your debug output I can see that GpgOL appears to cause the crash in the
GetCustomUI function.

This is a very simple and static function that is called very often.

Is this issue reproducable for you? What were you doing exactly when it crashed?

(From the debug output it looks like you've opened the Tasks view but this works
ok for me)

Do you have any other Addins installed in Outlook?

Hi,

since April there are 14 crashes recorded in windows event log, one occurred in
function btnDecryptLarge all others in function GetCustomUI.

It happens occasionally when changing between views. So it's not easy to
reproduce the behaviour. Even the log is not very useful because there are no
timestamps in the log entries to check it against windows event log.

There are other 6 active plugins installed.

If you need more info’s, please let me know.

KJ

Wildly clicking around and changing components in GpgOL for quite some time I
was able to trigger this crash once (right before I was about to give up)

So there definitely is something here. Probably a threading / timing thing as it
is so hard to reproduce. Should not be though as all the extension code runs in
Outlooks main thread.

I've tried to reproduce it a second time but failed. Even with a script changing
components and opening encrypted mails in Outlook I was unable to reproduce it a
second time.

If I don't find more I'll add some more trace code in the debug output for a new
release. That should help us to at least tell us where it crashes in that function.

So I'm going to wait for a new release with more tracing capabilites.
Thanks so far.
KJ

Hi, any plans for the next release?
Best regards
KJ

Just to give an update:

since June I had 24 messages of type without any encryption/decryption

Fehler bei der Ausführung des Add-Ins. Outlook ist während des Rückrufs
'GetCustomUI' der Schnittstelle 'IRibbonExtensibility' beim Aufrufen des Add-Ins
'GpgOL - The GnuPG Outlook Plugin' abgestürzt.

and one of the folling two

Fehler bei der Ausführung des Add-Ins. Outlook ist während des Rückrufs
'btnDecryptLarge' der Schnittstelle 'IRibbonControl' beim Aufrufen des Add-Ins
'GpgOL - The GnuPG Outlook Plugin' abgestürzt.

Fehler bei der Ausführung des Add-Ins. Outlook ist während des Rückrufs
'btnDecrypt' der Schnittstelle 'IRibbonControl' beim Aufrufen des Add-Ins 'GpgOL

  • The GnuPG Outlook Plugin' abgestürzt.

Thanks for the info (and again apologies for your trouble)

btnDecryptLarge and btnDecrypt are also functions that only fetch resource data
like GetCustomUI. I don't understand why they would crash only some time and not
always.

From looking at the code the only possible problem I see is that an invalid
result pointer is passed to that function. There is not check for that. I'm
adding one.

With regards to getcustomui:

In the current mime-addin development branch I'm currently working on I have
modified the ribbon ui function to use a dynamically allocated string. But this
should not the problem because the locale strings should not change.

Another theory that I need to check is that the pointers to the localized string
I use there are not guaranteed to be valid when they are used in the sprintf
call. They should be, but maybe there is a problem with our gettext
implementation. So I'll reduce the lifetime of the pointers to the function call.

Thanks for your quick reponse.

I've just uploaded a Test Version of a new GpgOL and documented it under:
https://wiki.gnupg.org/GpgOL/Development/Testversions

While the main focus for that Testversion is MIME support I've also added a lot
of debug output in the functions you see crashing:

http://git.gnupg.org/cgi-bin/gitweb.cgi?p=gpgol.git;a=commitdiff;h=7016fec9aef7be53f164829f7c76e28c6a83e228

If you are willing it would be a great help if you would install that version
and provide me with the gpgol debug log after you encounter the next crash.

They just might also be gone because of the changes mentioned in T1837 (aheinecke on Oct 13 2015, 12:06 PM / Roundup) but I
doubt it.

I just had another crash using your latest provided gpgol.dll.
See gpgol logfile and corresponging windows eventlog entry in the file included.

Thanks!

Did you obtain the log right after the crash or have you started / shut down
outlook once after the crash? (From the debug output it looks that way).

Or did the crash happen when closing Outlook?

I've just commited a change to the logging format so that the current UTC Date
Time is included in the log and it can be better correlated with EventLog entries
and I don't have to ask such questions in the future ;-)

I've also added a guard against an invalid parmeter in the function now reported
to crash (The Application ItemLoad event handler) and even more debug output in
that function (because I doubt that the invalid parameter caused the crash).

I'll give you a ping here when I've uploaded a new version.

Outlook reported the problem and a message box appeared stating "searching for
the cause of the problem". Outlook then restarted itself. After terminating
Outlook I assembled the log files.

The most interesting lines should be around line # 3152 which is presumably the
very last line before/during the crash.

So I'll wait for the new version :-)

Ok. Thats what I thought.

The problem is that
" 90695/8872/mailitem-events.cpp:Invoke: Unloaded. " Is unrelated to the
function the event log says caused the crash (application-events.cpp:Invoke).
And is the usual last line of a "normal" mail item unload..

In Application Events the first log entry would have been "Installing event sink
on mailitem: ..." [1]

But as we did not see that before the crash I've added a check if parms is NULL
in that call (Which according to msdn it should never be and that function is
called by outlook and not by us). And added debug output before the first
function call in that function (But that function call is just an Error wrapper
around a QueryInterface call which should also never ever crash ;-) )

Weird.

1:
http://git.gnupg.org/cgi-bin/gitweb.cgi?p=gpgol.git;a=blob;f=src/application-events.cpp;hb=560cea7e5bbf7f0404e4f1977b42710245f26b1f

Thanks for the answer. Is there another (beta) dll for download or should I wait
for the next release?
TIA KJ

I just installed the version and as soon as there are new results I'll come back
to you.
Thanks

Had another crash today. The last steps were: exported contacts to a local file
and when done I switched to inbox folder. Then Outlook crashed and restarted itself.
Please see windows evenlog entry and gpgol log file.
Best regards kj

Now it's definitely exporting contacts. Today I didn't even switch to inbox.

looking at the data from 20152029.tar.gpg:

At the point where the Eventlog reports the crash GpgOL was not doing anything
according to the debug output. I'm not sure what the Windows event log wants to
tell me with "gpgol.dll_unloaded" in the error message.

And with exporting contacts. There is absolutely no code in GpgOL that does
anything with contacts. :-/

I've talked with Werner (who handled gpgol development before me) about this bug
and that I am clueless how a static function like GetCustonUI could sometimes
crash and sometimes not. And he thinks that the EventLog information may just be
wrong.

E.g. It just prints the last function called in gpgol. While the actual problem
might be caused by a different addin.

I should probably ask on the gpg4win-users mailing list if others are seeing
those random crashes too. But with the frequencies you are seeing I would expect
that we had more reports about this.

If you can reproduce this with exporting contacts, maybe you can disable the
other addins you are using in Outlook and check if it still crashes?

Or disable GpgOL and check if the crash dissapears?

The eventlog messages as of today are:

Fehler bei der Ausführung des Add-Ins. Outlook ist während des Rückrufs
'0x0000FAB5' der Schnittstelle 'ApplicationEvents' beim Aufrufen des Add-Ins
'GpgOL - The GnuPG Outlook Plugin' abgestürzt.

followed by

Name der fehlerhaften Anwendung: OUTLOOK.EXE, Version: 15.0.4763.1000,
Zeitstempel: 0x55f7f203
Name des fehlerhaften Moduls: OUTLOOK.EXE, Version: 15.0.4763.1000, Zeitstempel:
0x55f7f203
Ausnahmecode: 0xc0000005
Fehleroffset: 0x0016ed2c
ID des fehlerhaften Prozesses: 0x1704
Startzeit der fehlerhaften Anwendung: 0x01d112f3b4588f4c
Pfad der fehlerhaften Anwendung: C:\Program Files (x86)\Microsoft
Office\Office15\OUTLOOK.EXE
Pfad des fehlerhaften Moduls: C:\Program Files (x86)\Microsoft
Office\Office15\OUTLOOK.EXE
Berichtskennung: 700aef2d-7f14-11e5-920b-2c4138a83b6e

I'm to check exporting contaxts by disabling addins as you suggested.

Now Outlook crashed while trying to modify addins.

Fehler bei der Ausführung des Add-Ins. Outlook ist während des Rückrufs
'OptionsPagesAdd' der Schnittstelle 'ApplicationEvents' beim Aufrufen des
Add-Ins 'GpgOL - The GnuPG Outlook Plugin' abgestürzt.

Name der fehlerhaften Anwendung: OUTLOOK.EXE, Version: 15.0.4763.1000,
Zeitstempel: 0x55f7f203
Name des fehlerhaften Moduls: OUTLOOK.EXE, Version: 15.0.4763.1000, Zeitstempel:
0x55f7f203
Ausnahmecode: 0xc0000005
Fehleroffset: 0x0016ed2c
ID des fehlerhaften Prozesses: 0x2dd0
Startzeit der fehlerhaften Anwendung: 0x01d11321b1369144
Pfad der fehlerhaften Anwendung: C:\Program Files (x86)\Microsoft
Office\Office15\OUTLOOK.EXE
Pfad des fehlerhaften Moduls: C:\Program Files (x86)\Microsoft
Office\Office15\OUTLOOK.EXE
Berichtskennung: 3d154856-7f1e-11e5-920b-2c4138a83b6e

Both those Event log entries are bogous.

If you take a look at the application events callback:
http://git.gnupg.org/cgi-bin/gitweb.cgi?p=gpgol.git;a=blob;f=src/application-events.cpp#l58

In case it is called with NewMailEx (0x0000FAB5) or OptionsPagesAdd (0x0000F005)
as the event log entries suggest.

The only lines executed are:

USE_INVOKE_ARGS (which is a helper macro to reduce compiler warnings. Does nothing)

log_oom_extra ("%s:%s: Unhandled Event: %lx \n", SRCNAME, func, dispid);

and
return S_OK;

There is simply no way that this can crash.

The previous crash you've reported in ApplicationEvents was for the ItemLoad
event. This does some more stuff so I accepted that there might be a crash in there.

But there is no way that the Event handler could crash in the other two events
from T1837 (kjathome on Oct 30 2015, 04:56 PM / Roundup) and T1837 (kjathome on Oct 30 2015, 04:46 PM / Roundup)

I've come up with a theory to explain what we are seeing here:

You have another addin that does some things asynchronously (in a different
thread) this addin then makes a callback into the Outlook Object model. This is
not supported and you should not do this according to documentation. But it
might just work.

Assuming (because you don't see random crashes where gpgol is not involved) that
this works in the majority of cases but when outlook is busy executing third
party code (like gpgol) this causes the crash.

In that case Outlook would think that it crashed in gpgol as the main thread of
Outlook was executing gpgol code at the time of the crash although gpgol did
nothing wrong.

This theory could be validated if you leave GpgOL active but start to disable
other addins and check that the crashes disappear.

I've added werner to the nosy list. Maybe he has another idea.

Just turned off all addins but gpgol and export of contacts worked. Enabled
again all addins and export of contacts worked without problems. There must be
some other influences.

The only third party addin besides gpgol (and those of Microsoft) I've installed
is PDF Architect 3 which I disabled. During the step of disabling another
crashed occured. Now I'm going to see waht happens.

just installed the free version of PDF Architect 3 in a test VM and after
clicking around a bit I got a crash in Outlook.

Then restarted and got an "Runtimeerror" in the GetCustomUI callback of PDF
Architect 3. (These errors are normally not shown if you don't enable them under
"Erweitert -> Entwickler -> Add-In-Benutzeroberflächenfehler anzeigen")

This addin looks fishy.

So it seems as if the cause has been found. I uninstalled PDF Architect and
hopefully there will be no more crashes.
Thanks
KJ

I clicked on an e-mail today and it got decrypted (although others didn't). This
e-mails have been left decrypted (see T1106). So I wanted to disable gpgol
and when I tried to do so Outlook crashed again.
Because I deinstalled PDF Architect there is no such addin!
Unfortunately there must be another reason.
I'll append gpgol.txt, an excerpt of windows eventlog and screenshots of the
addins still activated in archiv.tar.gpg.

Because I had serveral crashes the last 2 days I decided to disable gpgol add-in.
I'll see what it's going to happen the next days.

I clicked on an e-mail today and it got decrypted (although others didn't).

That means that it was a valid PGP/Mime or PGP/Inline mail and you encountered
the new handler code which works similar to the old mail handling we had for
Outlook 2007 and earlier in that it decrypts / verifies automatically and then
shows the plaintext in the mail body.

This e-mails have been left decrypted (see T1106). So I wanted to
disable gpgol

It should not have been left decrypted. GpgOL now prevents that. If Addin
deactivation was involved you might have run into T2138 which I only fixed
on Monday and the fix for this was not in your version.

Pic2.png shows the message we inject in the Mail Body when we encounter Outlooks
"Write event" to avoid just such a leak.

The latest Version (Currently beta-85) also has a fix for the confusing "The
properties of the Mail have changed do you want to save dialog" (Where clicking
yes also brings up the message of Pic2.png)

http://git.gnupg.org/cgi-bin/gitweb.cgi?p=gpgol.git;a=commit;h=452477949fe2f1d8ca36ebbad31c6f3c6607e30e

and when I tried to do so Outlook crashed again.
Because I deinstalled PDF Architect there is no such addin!
Unfortunately there must be another reason.
I'll append gpgol.txt, an excerpt of windows eventlog and screenshots of > the
addins still activated in archiv.tar.gpg.

The debug output / event log match here. It crashes on Release in the destructor
of the Addin object. There might be a bug there if we Release / delete an
invalid object. I'll investigate and test this some more. Thanks.

Because I had serveral crashes the last 2 days I decided to disable gpgol
add-in. I'll see what it's going to happen the next days.

Ok. Please let us know how it works out and if you still see random crashes. And
thanks again for your feedback / testing.

Hi,

The "crash on disable" from T1837 (kjathome on Nov 03 2015, 06:44 PM / Roundup) was indeed a bug in gpgol. I've fixed it
with rev. 4f8c746e (included in beta100 and later). It only happened under
circumstances that did not occur in my development environment.

Have you seen crashes while gpgol was disabled?

Regards,
Andre

Hi,

thanks for your reply. No, there was no crash since disabling gpgol. I even
exported my contacts every day without any problem.

Is there a testversion available?

Kind regards,
KJ

Yes there is a new version available from the usual place. beta 103 is currently
the latest. I'll probably publish a beta installer containing that version later
today.

Thanks. I found it. WHat's the difference between gpgol in
beta folder and that one in mime-send?
After replacing the dll I tried to enable gpgol but I had bno success so far.
There is a run time error reported when loading the addin. I also ran
ProcessMonitor and there is probably a missing file "C:\Program Files
(x86)\GNU\GnuPG\pub\api-ms-win-appmodel-runtime-l1-1-0.dll".
There are screeen shots in file uploaded.

Kind regards
KJ

I can reproduce the problem that this dll does not load.

Weird the same version compiled directly works for me. I'll investigate what
happens on the build system / with the buildscript.

A change I did for the 64 bit version of Outlook caused the load problem. This
did not happen for my development builds as they were not run cleanly (in
contrast to the builds I upload)

Fixed with https://files.gpg4win.org/Beta/gpgol/1.3.0-beta104/

Apologies and thanks for your feedback!

Ah and with regards to the mime-send variant. That is a variant of GpgOL that
has experimental support to send PGP/MIME mails. (e.g. Mails that follow a
proper standard for crypto mails and are more interoperable with thunderbird and
gpgmail)

Then you won't have to encrypt the body anymore and add encrypted attachments
etc. but rather you just mark "this mail should be encrypted" and when you send
it it will be encrypted including all attachments etc.

Once we release 1.3.0 this will be the basis for the next version for now we
mainly use it for internal testing and as a proof of concept. The UI is not
where we want it to be. I'll write something about it in the wiki.

Btw. I've tried to explain a bit how the MIME Support in 1.3.0 works in the wiki
already: https://wiki.gnupg.org/GpgOL/MIMESupport

Ah and with regards to the mime-send variant. That is a variant of GpgOL that
has experimental support to send PGP/MIME mails. (e.g. Mails that follow a
proper standard for crypto mails and are more interoperable with thunderbird and
gpgmail)

Then you won't have to encrypt the body anymore and add encrypted attachments
etc. but rather you just mark "this mail should be encrypted" and when you send
it it will be encrypted including all attachments etc.

Once we release 1.3.0 this will be the basis for the next version for now we
mainly use it for internal testing and as a proof of concept. The UI is not
where we want it to be. I'll write something about it in the wiki.

Btw. I've tried to explain a bit how the MIME Support in 1.3.0 works in the wiki
already: https://wiki.gnupg.org/GpgOL/MIMESupport

Thanks for your notes. gpgol beta 104 now loads again.

Just a short update. Working with addin-options dialog now works fine with beta104.
But as soon as I'm exporting contacts Outlook crashes again.
Best regards
KJ

Just to recap:

  • You can export Contacts with GpgOL disabled.
  • When you have GpgOL enabled Exporting contacts Crashes Outlook.

How do you export contacts? I've tried with selecting "Personen (probably
Persons)" tab and dragged & dropped my contacts to a folder in the filesystem.
.msg Files for those contacts are created and no crash. I can switch back to
Mails, decrypt mails etc. no crashes for me :-/

This is with outlook 2013 and 2016 and either with or without an Exchange
Account. (But exchange without Active Directory)

Can you again send me a log of such a crash please? Maybe with all the added
debug output I can see something out of the ordinary.

Yes that's true, when disabled, all works fine.

In Outlook's folder tree view I select "Kontakte" and then
Datei->Optionen->Erweitert->Exportieren->In Datei exortieren->Weiter->Outlook
Datendatei (.pst)->Weiter->Weiter->specify file name for the export->Fertig
Stellen->OK.
If gpgol is active then Outlook usually crashes at that point or when changing
to the inbox.

I just replay the scenario enabling gpgol and susequently exporting contacts and
it worked - see latest Application view entries and last gpgol debug output.
In the file appended there are the application log entries since Nov. 13th
(Source: Outlook and "Application Error") and the relating gpgol log file if active.

Outlook is exchange based and connected to an AD.

Best regards
KJ

Datei->Optionen->Erweitert->Exportieren->In Datei exortieren->Weiter->Outlook
Datendatei (.pst)->Weiter->Weiter->specify file name for the export->Fertig
Stellen->OK.

\o/ This way I was able to reproduce the crash after switching back to the Inbox
and Outlook complained that GpgOL caused the crash.

Wow. This will be fun to debug, we are doing absoluetly nothing with contacts.

But I'm happy that you are able to reproduce crash.
Good luck for debugging.

Regards
KJ

I was able to reproduce this five times. It appears that time is also a factor
here. When I start GpgOL look at a mail, go to contacts ands export them I dont
get crashes.

But when I wait ~10 minutes after opening the contacts view I get the crashes
pretty reliably.

Funny thing is and I see from your logs that something similar happened at least
once for you that the last Debugoutput of GpgOL is way before the crash.

e.g.

  • switch to contacts at 18:30
  • wait 10 minutes
  • export contacts, switch to mail.
  • Crash.

Last debug output before the crash is from 18:30 eventlog shows the crash at
18:40 and the restart of gpgol and the startup procedure is logged at 18:40.

But the ItemLoad event where the EventLog says gpgol is crashing is what gpgol
should be getting once we switch back from the contacts view to the mail view.
But gpgol does not get it. I've added debug output in the first line of that
function and it is not called.
The handler for the ItemLoad event is also not deleted and still valid.

Next step will be for me to look at the address of GpgOL's event handler
function and at the address which is called when outlook crashes... I still
don't even have a theory what's happening here.

I understand whats happening here now. I still don't undestand the Why.
For my tests I've disabled all other Addons to rule out interference.

In the crashing case Outlook unloads GpgOL from it's memory. This happens
regularly with the test described in T1837 (aheinecke on Nov 16 2015, 08:07 PM / Roundup). But as the original Report
mentioned crashes at other points I'm not really sure what causes this but
Exporting contacts seems to be a good trigger.

This Unload does not call any of the Registered Cleanup methods like
"OnDisconnect" etc. and GpgOL is never Unregistered in Outlook. The only thing I
can see is that DLLMain is called with "PROCESS_DETACH". And that ProcessExlorer
no longer shows GpgOL as loaded.

Any callback outlook calls into gpgol, getCustomUI, ApplicationEvents ItemLoad
etc. will cause a crash as the memory behind those callbacks is invalid. This is
why we've seen crashes apperantly all over the place.

Ok now that we know the What. We have to figure out the Why. A websearch about
this has not brought up anything.

My current speculation is that there is some interference with out old
ExchangeExtensionCode that might be activated by exporting contacts (this dialog
looks really old).

Well but at least we are getting closer. In fact in my development version I
have a nice messagebox popup "Gpgol was unloaded Outlook will now crash" :-) But
yeah thats not really helpful...

I can confirm the behaviour related to time. When gpgol is enabled before
exporting contacts and then disabled I can do this multiple times (for at least
twice). When waited for some time gpgol is unloaded as soon as the "Fertig
stellen" has been clicked, which means beginning the export.
That's really weird...

As a workaround it's possible to disabled gpgol before exporting contacts.
After enabling gpgol it's possible to decrypt/verify encrypted mails without
problems.

I think that I found and fixed the problem.

There is a method COM addins have to implement to indicate weather or not it's
Ok for them to be unloaded. I totally forgot about that method as I've
implemented it years ago as part of the standard "stuff you have to implement
for COM".
This method used bad values to check if an unload is ok (which basically should
be never as long as we are not deactivated).

My current understanding is that the trigger here was that after exporting
contacts some internal cleanup code in Outlook checks if there are Addons that
are no longer needed and unloads them if they tell Outlook that this is Ok.
Which we dit. So Outlook unloaded us and any more calls to GpgOL crashed.

I could confirm with debug output that this was called right before GpgOL was
unloaded and we told Outlook that it's Ok to unload us.

This cleanup can probably happen under other circumstances, which would also
explain the random crashes you've seen before.

Thanks again for your patience and your excellent feedback in this issue which
made it possible to find and fix this.

The fix is:
http://git.gnupg.org/cgi-bin/gitweb.cgi?p=gpgol.git;a=commit;h=1362563c9370cc9c00463293a7f6eeb91b9424de

A binary with the fix is:
https://files.gpg4win.org/Beta/gpgol/1.3.0-beta108/gpgol.dll

There will be a gpg4win release with this Version soon.

Please let me know if you are still seeing crashes ;-) I could not reproduce any
more crashes with this version.

Thanks for the quick fix and your detailed answer.

I installed the new version and had nearly no problems: I successfully exported
contacts serveral times (even waiting more than 10 minutes) and de- and
encrypted emails multiple times.

There was only a crash at the very beginning when I started outlook and forwared
an email with encryption to myself. Outlook crashed but module MSPTLS.DLL has
been reported to be the cause of the failure.

In the log file of gpgol I noticed that there is a huge amount of messages
in.lock taken or released and the same for out.lock. Is it possible to disable
selectively these lines because it floods the disk and I'd like to have some
debug lines enabled if some problem might occur.

Best regards
KJ

There was only a crash at the very beginning when I started outlook and forwared
an email with encryption to myself. Outlook crashed but module MSPTLS.DLL has
been reported to be the cause of the failure.

I'll try it out.

In the log file of gpgol I noticed that there is a huge amount of messages
in.lock taken or released and the same for out.lock. Is it possible to disable
selectively these lines because it floods the disk and I'd like to have some
debug lines enabled if some problem might occur.

Yes just set the enableDebug registry setting of GPGOL
(HKEY_CURRENT_CUSER/Software/GNU/GpgOL) to 1
You currently probably have it at a much higher level.
This will disable the most spamming debug outputs and leave the important stuff
active.

I had all flags enabled (2047) and set it now to 1.

Thanks again.
KJ

After installing the lastest beta I had unfortunately several crashes of Outlook.
The crashes are reported for severeal modules. There was no crash in module
gpgol reported, nevertheless I disabled gpgol.
If there are some news - even no more crash - I'll give an update here.

Best regards
KJ

I installed the new gpg4win 2.3.0 release and activated gpgol. When answering an
email I had another crash reported in ntdll.dll. But I suspect that the crash is
related to gpgol even though it's not directly reported.
Now I'm going to leave gpgol disabled.
The corresponding logs are appended and might be that there are some hints inside.
Best regards
KJ

We don't see any more crashes in testing and we had some other people test
1.3.0. before the release. Is it crashing or does outlook freeze up / not
responding?

Just to ensure that we have comparible setups, have you enabled other plugins
again? If so which?

I'll take a look at your debug output to see if I find something out of the
ordinary.

It was a crash. Outlook has been terminated and restartet automatically (can be
seen in gpgol log).
Now I'm going to start with gpgol enabled and I'll enable all other plugins step
by step.

I had a look at your logs. Indeed I can see where it crashes, and it really
looks like gpgol did something at the time of the crash. It crashed after a Mail
was Loaded by outlook and before it was read. I've read the related code again
and could not find a problem.

If you are testing again anyway Please set your EnableDebug value to 1536. This
enables Debug output related to outlooks internal data model and could help.

After installing gpg4win 2.3.0 (GpgOL 1.3.0) I had no more crashes.
Thanks for your fix.

aheinecke removed a project: Restricted Project.

Great to hear that! And again let me Thank YOU for your incredible patience and
assistance with logs to help track down / fix this problem. This was really a
nasty bug.