I am using Optimum Online Webmail and everytime an attachment is emailed to me, it downloads as "viewattachment" and I have to manually change the name of the file AND the extension in order for it to open properly in the application used. I didn't use to have to do this and it seems it's only been recent, so I'm not sure what has changed. I am using the newest version of Firefox on a Mac OS X. The same thing happens with opening email in Firefox in Internet Explorer, so it's not a Mac problem. I also contacted Optimum and they said it's a Firefox problem. Lastly, I tried assigning the correct applications to use upon opening certain file types in Firefox preferences and that didn't work either. I still have the same issue. Please advise as soon as possible as it's quite annoying to have to do this all the time. Other than this problem, I think Firefox is the best browser out there.