[Users] Signatures don't seem to work

[mlist]

Hi,

I have no experience with digital signatures but I notice some people
use them and Claws Mail shows that. I also notice that each time I try
checking a signature it tells me "Key 0x... not available to verify
this signature" and the "--debug" output when this happens is:

mimeview.c:1298:creating thread
mimeview.c:1207:checking...
pgpmime.c:189:Checking PGP/MIME signature
mimeview.c:1243:waiting a while
sgpgme.c:469:data 0x7.... (5744 488)
mimeview.c:1163:mimeview_check_sig_thread_cb
sgpgme.c:110:err code 9
sgpgme.c:110:err code 9

Seems to happen for any signature.

I also tried answering "yes" to the message:

"This key is not in your keyring. Do you want Claws Mail to try and
import it from a keyserver?"

which resulted in:

Importing key ID ...:

   This key couldn't be imported to your keyring.
   Key servers are sometimes slow.
   You can try to import it manually with the command:

     "/usr/bin/gpg2" --batch --no-tty --recv-keys ...

and debug output:

alertpanel.c:221:called inc_unlock (lock count 0)
alertpanel.c:105:return value = 1
gpg: keyserver receive failed: Configuration error
pgp_viewer.c:235:res 2

Why is all this happening? Is it normal or am I doing something wrong?

I have some vague memory that checking signatures used to work a few
months ago.

In case I am doing something wrong:
How can I use this functionality correctly? (docs?)