Got small problem with my browser.

Sometimes when I enter a address in address bar, firefox asks me to download the file (index.php for example) instead of running that file in browser. What can be the cause of this problem?

Any idea?

 

Depends on the site you are visiting more than the browser.

I have seen this behavior in both IE and Firefox when you try to access directly the Blogger default RSS file or visiting a site which has not set properly on-site files compression.

 

when browsing a site downloading a index.php file or .php means the site you are visiting has DNS issue and havent been fully resolved or have namebinding problem.

 

I think It's not your browser problem but it's server of the site problem

 

Do one thing. Uninstall firefox and reinstall it. It hardly takes few minutes. May be this will help you. If the problem solves then its fine, if not then its for sure thats a server problem!!

 

That does help.
it is a server problem.
My suggestion- Notify the owner/admin of the site.
P.S: IE8 Beta is waaay better that Firefox.

 

I am pretty much sure that its not the websites problem because It often happens with all websites.

 

did you try Firefox and IE?? same problem?
then maybe reinstall can help if software problem

 

Try clearing your cache, history, cookies and temp file.