Try clearing your browser cache.

Tools > Clear Recent History... - hit Details and make sure only Cache is selected, then select Everything and hit the Clear Now button.

That won't work... FF4 must have a bug as my wife had the same problem when she opened that E-mail. And the E-mail was from Coldwater Creek. FF4 somehow wants to open aspx files (coldwatercreek) site in notepad. Something in that E-mail was corrupt.

Under TOOLS - Options - Applications you will see a aspx file and your choices for that is notepad or download. No other choices and you can't delete it. If you just upgraded, you need to find out how to SAVE your bookmarks as you must delete FF4, I reinstalled 3.6. I deleted and chose to remove all personal setting. You can try to reinstall FF4 and see if that works. If not, try reinstalling 3.6 but it might erase your cookies and bookmards (so see how to save bookmarks). I tried reinstalling FF4 but that didn't work. I deleted FF4 and went back to 3.6 but forgot to save the bookmark files (and it's not the bookmark file in the folder) I was able to get a 6 month old bookmark file from an old profile. P.S. You can use IE and Coldwater Creek works...

It's not a cache problem, it's a file association problem. I don't know how to fix it. Developer - Help!

This issue has been resolved. Please let me know if you are still experiencing any problems. Thank you for your patience.

Thanks for your response Matt. I can now correctly load coldwatercreek.com. But I still have the problem on gpt.com.au. What was the problem at coldwater creek? Was it a problem with FF? Or the web site? How come the sites mentioned work fine in IE and FF 3.6, but not FF 4? Thanks for your help.

The problem was both FF and CWC. It has to do with the mime type being provided by our web server making FF try to download the website as a file. We made the correction on our side to remedy the issue. This as only occurring in FF4 on windows based machines. Hope that helps.

A BIG THANKS to all you guys who helped resolve this problem. The loss of Coldwater Creek really didn't bother me a whole lot but that was the last straw for my wife in a long string of computer 'problems' we were having in transferring our old files to a new computer. To access Coldwater Creek for her, I switched browsers to I.E. That switch caused a whole new batch of problems in itself. I was so glad to see the resolution at FF. I've switched back, can access Coldwater and have all my Bookmarks like I had them for several years on previous versions of FF. Now if I can persuade my wife to come back to the computer everything hopefully will settle back down. (And I know you can't help with THAT problem! :) )

Thanks Matt. I'm guessing you're the web guys for coldwater creek? I'm glad you've fixed the problem for your site, but the problem with FF4 still remains - it's changed it's behaviour from FF3.6 on how it handles asp(x) sites. FF3.6 handled them in the same way as htm(l), but FF4 doesn't. How do I raise this issue with the FF4 developers to get FF4 to behave the same way as FF3.6?

I am having this problem trying to open a benefit statement on my extended health insurance site. It usually opens as a pdf and does so in Safari (I'm on MAC) but in Firefox I get an error message saying: Users/******/Desktop/EOBViewer-6.aspx could not be opened, because an unknown error occurred. Try saving to disk first and then opening the file.

I have no way to save to disk from the website. I'm not sure if this is with other sites - I'll check and let you know. Thanks!

Firefox 5.0, running on XP SP3, and I'm having a major problem with .ASPX files as well.

I am trying to download several .ASPX files from ImperialOil.ca (MSDS Sheets for my company), and I get nothing - the only thing I can do is save them, but I can't open them with ANYTHING. Internet Exploder won't even open, Firefox just keeps trying to open new tabs, Notepad just shows the raw data (pages and pages of it!).

I tried changing the action in tools/options/applications list, but the only options it will let me do are "Save" or "Always ask". It won't even let me use another program to open the files.

I've sent an email to the company, but I'm more suspicious that the problem may be with my computer, since IE doesn't work for them, either. Any ideas?