[Mediawiki-l] Article path error

[lonelyprophet at hotmail.com]

Hi,
I'm having a second problem which seems to have come from nowhere too 
(again, no changes to DB structure or files my end).
The path to articles in my wiki has altered, and links no longer work.

The working form should be: index.php?title=pagename
But this has now changed to a default: index.php/pagename

Does anyone know where this can be fixed? I have no idea which files to even 
look at...

Thanks in advance!