An empty email cannot be signed or encrypted


I recently got the message:
An empty email cannot be signed or encrypted

When I open Outlook 365 gpg4win 4.02. want to sign or encrypt something.

All this under Windows 11:

I had already uninstalled all addins and also uninstalled and reinstalled gpg. It came all of a sudden.

Warm greetings

I’ve tried a few things now. Reinstalled Office, reinstalled GPG4win, reset Windows 11 with recovery when still worked. Nothing helped.

Finally I tried all GPG4Win backwards. With version gpg4win 3.1.5-1 I can sign and encrypt again.

Was there an Office update that gpg4win can’t handle? Or where is the mistake?

Hi Harald,

something must have changed if it worked and then stopped working.

  • I assume that it did not was the Gpg4win version, so it must be something else.
  • Additionally your key material stayed the same.

Yes this could have been an update with Outlook or Windows itself.


It must have changed, because the old Gpg4win 3.1.5 version works.

Nothing had changed on my computer. I was able to sign emails a few minutes earlier. And when I wanted to answer the next email two minutes later, it didn’t work anymore!

I know someone on the forum who also has this message.

This seems to be a defect caused because GpgOL cannot create some temporary files, it wants to use in some settings. In most setups, it seems to work fine.

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