package-list-packages and gpg in emacs 27.1

[Rainer Thiel]

I have just installed emacs 27.1 for windows which generally seems to
work fine with my configuration.  I have detected two problems though,
which might be just one:

1. When I call package-list-packages, I get the message «apply:
Searching for program: No such file or directory, gpg2».
2. When I try to open an encrypted file like foo.org.gpg, I get the
message «file-truename: Wrong type argument: arrayp, nil»

I suspect this is connected with Gpg4win (or my configuration for it).
In fact, there is no programme gpg2.exe on my system (but there is
gpg.exe).  I do not understand why package-list-packages needs gpg(2).

Can someone please help me understand what I need to configure to get
things right?

Thanks in advance

Rainer
-- 
Prof. Dr. Rainer Thiel
Institut für Altertumswissenschaften
07737 Jena, Germany (EU)
r.thiel@uni-jena.de