hello, your useragent (the information the browser sends to websites to identify its version) - apparently mistakenly - shows you're on firefox version 3.5.8. probably some sort of toolbar or adware has overwritten it. please refer to this article in order to reset the user-agent settings in firefox: How to reset the default user agent on Firefox

The information presented there explains what to do in Windows. Is there any step by step info for Mac?

it is the same procedure on both systems, there shouldn't be a problem following the steps mentioned in the article to reset your user agent...

I've done each step and still saying I need to upgrade. Currently I'm running Firefox 18.0.2 but somehow I'm seen as not. Can't connect for instance to Icloud.

when you go to http://browserspy.dk/useragent.php which UserAgent from header does it show - does it end with Firefox/18.0? if not you could also try to generally reset firefox: Refresh Firefox - reset add-ons and settings

It does end with Firefox/18.o

What is the current user agent as shown on the browserspy.dk site?

Did you reset all general.useragent prefs to the default?

If you do not keep changes after a restart then see:

• http://kb.mozillazine.org/Preferences_not_saved

Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

• Firefox > Preferences > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems:

• Firefox > Preferences > Privacy > Cookies: "Show Cookies"

I'm sorry I hadn't restarted my computer. After restarting firefox/Icloud is now working. Thank you very much for your help!