[pmwiki-users] "Not Found" - Error

[Mike]

Hello group,
after having set up my private group following the help I received
yesterday, everything looked perfectly - until I went into simply
editing the main page (subdomain.server.com/GroupName/HomePage).

Unter this circumstance, a very strange thing happened: it is possible
to edit parts of the page (like inserting one letter), but it was not
possible to make larger changes (changing some paragraphs etc.). It also
seems that the error will usually happen when I fill in something into
the "Author" and "Description" fields - not if I leave them empty.

This behavior is reproducable. When I try to make larger edits and
insert Author/Description, I get this error:

> Not Found The requested URL /GroupName/HomePage was not found on this
> server.
> 
> Additionally, a 404 Not Found error was encountered while trying to
> use an ErrorDocument to handle the request.

Where could I look for the causes of this error and for a solution?

Thanks,
Mike