mrmarkuz
(Markus Neuberger)
6
Sorry for late answer.
Please try to add vers=1.0 to your mount line like
mount -t cifs -o vers=1.0,username=xy,password=yx //server/share /mnt/mountpoint
to check if an old protocol is the problem.
Maybe you have custom templates on one of your servers that keep the old version protocol?
Another thread with same error: