Hi
FYI here is what I did to resolve:
running gpg.exe and gpg-agent.exe as Administrator and XP mode....
gp-agent:
set service Priority to REALTIME
Disabled Windows UAC virtualization.

OK, I identify the problem.

But this problem remains for several versions for some time. I tried to find out the source of this "new option" in the communication, but I could not find anything about "GPG Agent" in the source code of openssh.

Sorry for the late answer, but I have been busy. Actually this happened against several ssh versions, for some time now.

For information, I can’t reproduce here, either with GnuPG 2.2.17 / Pinentry 1.1.0 or with a fresh build from the tip of the master branches. Both pinentry-tty and pinentry-curses prompt for the password as expected, independently of whether the file to decrypt is specified as an argument or sent through standard input.

@dkg, I changed the title and adjusted the description to more accurately describe the situation.

@skeeto can you edit the summary/title of this ticket to better reflect what you think the underlying issue is?

Those changes make the script work for me, specifically passing the input as an argument and not through standard input. Digging more, it looks like the underlying issue is related to using pinentry-tty (my case) or pinentry-curses when passing the OpenPGP input via standard input. This causes pinentry to give up before prompting. For pinentry-tty it fails with "ERR 83886340 Invalid IPC response" and pinentty-curses fails with "ERR 83918950 Inappropriate ioctl for device".

Thanks aheinecke and dkg.
I havent been able to replicate the fault using the command line (using the exact same command and options that our program is calling)
however our R&D dept have,
The next time it fails and we can replicate it we will try the --homedir fix and see if thats it.
Its the same user in the program and command prompt so we dont think its a certificate issue.

I'm also not sure how to classify this issue. I'm giving it low priority for now as we do not have the info to determine if this is a program error.

Thanks for clarification.
However, CCID_CMD_TIMEOUT should be then based on BWT value reported by the card/reader, as bulk_in() function will still timeout if BWT is longer than 5 seconds.

Thanks for pointing me in the right direction. I was confused by the hard-coded timeout value and got it all wrong.

I realized that it's a product of token. Then, I suggest that implementing time extension correctly, if some operation doesn't finish in BWT (block waiting time).

In general, if it requires more time, a reader can reply with time extension.

What's Trustica Cryptoucan?
In general, if it requires more time, a reader can reply with time extension.

All my keys are RSA 4096. It worked fine with OpenPGP smart cards and with two Yubikey 5. On all devices a set of RSA 4096 keys were geneated on the device itself. Only one card failed. But even the card which failed, generated at least the signature key in RSA 4096.

Please let us know what kind of key and how large, like RSA-4096 or ECC Brainpool.
For RSA 2048 or larger, yes, it takes too long.

I disabled the dependency rules for the figures (it's only enabled for maintainers).

Which SSH client are you using?

It's complicated to have a good solution, because we need to change assumption (serial number identifies keys).

Hello again - can I ask about the status? Or should I consider this as a no-fix? Anything I can assist with?

As this update lists multiple issues and following fixes for them, maybe it was resolved by Microsoft?

But sadly I can't see any problem with the mail. Looking at the source of the mail it has the image as one attachment. That attachment is displayed. There are no other attachments part of the mail and so other clients also only show that one attachment.

I have sended the email...

Without more reports and without the info needed to analyze this further I'm lowering the priority.

Closing this as invalid until the info requested in the last comment is provided.

I've tested it with Gpg4win-3.1.7, too and it works for me so something must be special.

this error comes to me when I try to decrypt a message and I get this message

For what I use, please refer: https://tracker.debian.org/pkg/gcc-9

Which one version gcc 9 you've been using?
May I see gcc -v ?

@gniibe already wrote: “With gcc-9 in Debian experimental, everything goes well.”

BTW: fedora corp provides already free access to build envs with gcc 9 which can be easily integrated with CIs.

What you mean " it is not reproducible for u"?
Did you try to use gcc 9 and you had no problems compiling gnupg or you don't have access to build env with gcc 9?
Try to google to "gcc 9 pragma" and you will find several discussions and patches done by people fixing similar issues.