This is most likely a browser problem. I assume that your browser is somehow set so that "Save Link As" is the default as opposed to "Open link". This does not seem to be a software problem.
I've found this entry while searching for a problem I've just encountered. Not sure if it's the same issue, but it sounds similar.
I've recently done a substantial update to the wikipedia page for the rock band 'Love/Hate' (http://en.wikipedia.org/wiki/Love/Hate). When I tried to go to the page today, I get a file download prompt for a file called 'hate' with no extension. The resilt is a 12k binary file that I can't decypher.
I'm guessing that the problem is related to there being a forward slash in the page title. I didn't create the page this way, I simply edited the existing page. However, I've had no problem up until now, it's only today that I suddenly can't access the page. Also, looking at the page for the band 'AC/DC' (http://en.wikipedia.org/wiki/AC/DC) which has exactly the same title structure for the same reason, works fine.
I am using the same browser installation (IE 6.0.2900.2180.xpsp_sp2_gdr.070227-2254) on the same laptop as all previous times I've accessed. I am at work today using the connection here, whereas over the weekend I was connecting from home. But I also connected from work last week without problem and I'm not aware of any changes to the technical environment (I'm Head of IT here so I would hope someone would tell me!). I can confirm that my browser defintely isn't set to use 'save link as' by default. I've also tried right clicking the link and using 'open' or 'open in a new browser' to confirm there is nothing like that going on.
I can't access the page at all, so I'm not even able to edit the page title. Very weird. I have this page on my watchlist, and acording to that no-one has edited it since I last made an update (username 'ThePaintedOne') and it was certainly working for me after I made that update.
I'll check when I get home to see if a different internet connection makes any difference to this.
Screenshot of file download prompt.
Don't know if it helps, but this is a screenshot of the file download prompt after I clicked on the 'Love/Hate' link visible on my watchlist. I've tried other methods of getting to the page with the same result, so its not the watchlist in error.
(In reply to comment #2)
What site? What download? More details, please! Do you have "external diff"
switched on in your preferences?
Well, it says the file to be downloaded is "index.php". It dosen't happen when I do it as an anon. ~~~~