Writing to a foreign group

[Hermann]

Hi,
my main news server is news.online.de, the server of my German ISP.
However: I've subscribed to a foreign group:
news.mozilla.org:mozilla.support.accessibility.
I can read this group, but I have to realize that I'm not able topost a
news there.
When I open a new post, put in the group - with and withouth the full
path - I always get the message that it cannot be sent, because there is
no such group; this is obviously wrong.
How can i send to this group?
I tried to put it into my .gnus file under:
(setq gnus-secondary-select-methods
   '((nntp "news.mozilla.org"))   
   '((nnml "private")))
But only the mail selection method is accepted. I get the message:
"Error in ~/.gnus: symbolp"
when starting gnus.
So what to do? Why are things so terribly complicated? :-(
Hermann

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