What Version of Windows do you use? If you use an older Windows (pre 7) please follow this guideline: https://wiki.gnupg.org/Gpg4win/releases/3.0/notes

Jochen, I am currently using Windows 10 version 1607 (OS Build 14393. 1230).

To test, I installed the previous release of GPG4Win (2.3.4) and was able to install it and run it as I would expect to.

Hey @cprezalor, the new Gpg4win Version was just released. Can you please download it and check if this error still persists?

Jochen, I've uninstalled the previous version and now installed the most current release. Unfortunately it did not result in a successful run. Here are the details from the event log.

Having said that, on a windows 7 computer it installed perfectly well and I had no problems launching it. I haven't had a chance to run it on a basic windows 10 installation, just my workstation, which has its fair share of oddities installed.

(Here's a list of what's installed on my system in the event there's an obvious conflict or problematic program

Log Name: Application
Source: Application Error
Date: 11/21/2017 8:04:15 AM
Event ID: 1000
Task Category: (100)
Level: Error
Keywords: Classic
User: N/A
Computer:
Description:
Faulting application name: kleopatra.exe, version: 0.0.0.0, time stamp: 0x00000000
Faulting module name: kleopatra.exe, version: 0.0.0.0, time stamp: 0x00000000
Exception code: 0xc0000005
Fault offset: 0x000543b2
Faulting process id: 0x2754
Faulting application start time: 0x01d362c9399f0c6e
Faulting application path: C:\Program Files (x86)\Gpg4win\bin\kleopatra.exe
Faulting module path: C:\Program Files (x86)\Gpg4win\bin\kleopatra.exe
Report Id: 3900ad8b-9d05-4dfa-af6a-256baae00f57
Faulting package full name:
Faulting package-relative application ID:
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">

<System>
  <Provider Name="Application Error" />
  <EventID Qualifiers="0">1000</EventID>
  <Level>2</Level>
  <Task>100</Task>
  <Keywords>0x80000000000000</Keywords>
  <TimeCreated SystemTime="2017-11-21T13:04:15.629379300Z" />
  <EventRecordID>1093843</EventRecordID>
  <Channel>Application</Channel>
  <Computer></Computer>
  <Security />
</System>
<EventData>
  <Data>kleopatra.exe</Data>
  <Data>0.0.0.0</Data>
  <Data>00000000</Data>
  <Data>kleopatra.exe</Data>
  <Data>0.0.0.0</Data>
  <Data>00000000</Data>
  <Data>c0000005</Data>
  <Data>000543b2</Data>
  <Data>2754</Data>
  <Data>01d362c9399f0c6e</Data>
  <Data>C:\Program Files (x86)\Gpg4win\bin\kleopatra.exe</Data>
  <Data>C:\Program Files (x86)\Gpg4win\bin\kleopatra.exe</Data>
  <Data>3900ad8b-9d05-4dfa-af6a-256baae00f57</Data>
  <Data>
  </Data>
  <Data>
  </Data>
</EventData>

</Event>

Log Name: Application
Source: Windows Error Reporting
Date: 11/21/2017 8:04:16 AM
Event ID: 1001
Task Category: None
Level: Information
Keywords: Classic
User: N/A
Computer:
Description:
Fault bucket 1997010341518692083, type 1
Event Name: APPCRASH
Response: Not available
Cab Id: 0

Problem signature:
P1: kleopatra.exe
P2: 0.0.0.0
P3: 00000000
P4: kleopatra.exe
P5: 0.0.0.0
P6: 00000000
P7: c0000005
P8: 000543b2
P9:
P10:

Attached files:
\\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERB4A2.tmp.WERInternalMetadata.xml

These files may be available here:
C:\ProgramData\Microsoft\Windows\WER\ReportArchive\AppCrash_kleopatra.exe_56ee153ea9ea8e46d487e643513d7516833ce5e7_eb130d14_7cf0b88a

Analysis symbol:
Rechecking for solution: 0
Report Id: 3900ad8b-9d05-4dfa-af6a-256baae00f57
Report Status: 0
Hashed bucket: 56faf5ab28d8dc219bb6ce533300cef3
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">

<System>
  <Provider Name="Windows Error Reporting" />
  <EventID Qualifiers="0">1001</EventID>
  <Level>4</Level>
  <Task>0</Task>
  <Keywords>0x80000000000000</Keywords>
  <TimeCreated SystemTime="2017-11-21T13:04:16.826602700Z" />
  <EventRecordID>1093844</EventRecordID>
  <Channel>Application</Channel>
  <Computer></Computer>
  <Security />
</System>
<EventData>
  <Data>1997010341518692083</Data>
  <Data>1</Data>
  <Data>APPCRASH</Data>
  <Data>Not available</Data>
  <Data>0</Data>
  <Data>kleopatra.exe</Data>
  <Data>0.0.0.0</Data>
  <Data>00000000</Data>
  <Data>kleopatra.exe</Data>
  <Data>0.0.0.0</Data>
  <Data>00000000</Data>
  <Data>c0000005</Data>
  <Data>000543b2</Data>
  <Data>
  </Data>
  <Data>
  </Data>
  <Data>

\\?\C:\ProgramData\Microsoft\Windows\WER\Temp\WERB4A2.tmp.WERInternalMetadata.xml</Data>

  <Data>C:\ProgramData\Microsoft\Windows\WER\ReportArchive\AppCrash_kleopatra.exe_56ee153ea9ea8e46d487e643513d7516833ce5e7_eb130d14_7cf0b88a</Data>
  <Data>
  </Data>
  <Data>0</Data>
  <Data>3900ad8b-9d05-4dfa-af6a-256baae00f57</Data>
  <Data>0</Data>
  <Data>56faf5ab28d8dc219bb6ce533300cef3</Data>
</EventData>

</Event>

The registry key does not exist on my system, and neither does the c:\program files (x86)\GnuPG\bin directory. There is only the Share directory under c:\program files (x86)\GnuPG\

Having said that, I have a suspicion of what may be going on, and hopefully you can help confirm my suspicions.

Presently we have a group policy in place in our organization that prevents the execution of files under the Windows\temp directory. Typically this is not a problem for installers as they're usually executed from the downloads folder, desktop, or other location. However, we've had occasional problems with some installers that attempt to execute from the temp folders and have to make exceptions for those executables.

Does the GPG4Win suite, being made up of several different programs as best I can tell, attempt to execute files from one of the windows temporary locations?

[EDIT] Also, since the previous version appears to work properly on this same computer, would this have been something that was changed from a previous version?

Indeed. Since Gpg4win-3.0 Gpg4win uses the "official" GnuPG-w32 installer. This installer is bundled with Gpg4win and extracted during installation into the temporary directory and executed from there. So your problem is likely that GnuPG is not installed. As GnuPG is the core component of Gpg4win this will lead to a broken setup (although the error should be detected so I'll leave this issue open for that problem.

You can download the " Simple installer for the current GnuPG" from https://gnupg.org/download/index.html and install it manually. This should fix your problem.