Passwords...

Hi I have mozilla Firefox version 3.0.10 and for some reason it has stopped saving my passwords for the varius sites I visit regularly. It used to save them and I'm not sure if it's to do with Firefox or one of the security programs I use. I have Windows Advance System Care 3, Tune Up Utilities 2009, BT NetProtect Plus in association with McAfee and Malwarebytes Anti Malware. I haven't changed the settings on any of these so don't know if they are responsible for my passwords vanishing but any help would be appreciated, obviously I understand this is not a major security issues to my knowledge but if anyone can shed any light I'd be happy

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