GCC to Yahoo groups fails

[Eric S Fraga <e.fraga@ucl.ac.uk>]

Hello,

A while back (months), GCC stopped working when sending email using my
yahoo account.  GCC works with other IMAP servers, even Exchange acting
as IMAP, but not with Yahoo.  Below is the stack trace on error:

,----
| Debugger entered--Lisp error: (wrong-type-argument stringp nil)
|   string-match("^[^:]+:" nil)
|   nnimap-retrieve-group-data-early("yahoo" (nil))
|   nnimap-request-group("INBOX" "yahoo" t nil)
|   gnus-request-group("nnimap+yahoo:INBOX" t (nnimap "yahoo" (nnimap-address "imap.mail.yahoo.com") (nnimap-server-port 993) (nnimap-stream ssl)))
|   gnus-inews-do-gcc()
|   gnus-agent-possibly-do-gcc()
|   run-hooks(message-sent-hook)
|   message-send(nil)
|   message-send-and-exit(nil)
|   funcall-interactively(message-send-and-exit nil)
|   call-interactively(message-send-and-exit nil nil)
|   command-execute(message-send-and-exit)
`----

Can anybody point at some configuration error I may have made?  I
actually turn GCC off supposedly using "G c" on the group but that seems
to be ignored.  Setting GCC in the group configuration to something
nnimap+yahoo:Folder (for any folder, e.g. INBOX in example above) also
fails: it's ignored and the GCC line always looks like
nnimap+yahoo:Sent.

I'm using gnus from git.

thanks,
eric

-- 
: Eric S Fraga, GnuPG: 0xFFFCF67D
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