As reported in
https://wald.intevation.org/forum/forum.php?thread_id=2243&forum_id=84&group_id=11
a pubkey could not be imported and a new keypair could not be created with Gpg4win 3.1.13
it worked with 3.1.10 before.
The problem is a non-ASCII character in the user name of the windows account.
How to reproduce:
* Install Gpg4win (as User with Administration Rights)
* Add another account with an Umlaut,e.g. "Maus Münster" or "Östern"
(Short way on Windows 10: Settings/Einstellungen -> Kontos -> Family and other Accounts -> weiteren Nutzer.
Kenne Ameldedaten nicht -> lokales Konto)
* Login as other user, try e.g. gpg -v --quick-gen-key irgendwas
after the acceptance of passphrase the error message is
Schlüsselerzeugung fehlgeschlagen: No such such file or directory.