Windows 7 Live Mail 2011

Hello, I received a pop up box in Live Mail 2011 when trying to log in ...saying user name or password is incorrect.  I've had no problems up until this point.  After several attempts to log in without success, I rebooted the computer several times.  This didn't work either.  I called my internet provider and re-set the password... they also helped me reset the password on my Live Mail 2011 settings for that email account.  Again I tried rebooting and trying several times to log in...still not working.  After 5 hours of working with them and getting transferred to their tier 2 techs.. they concluded that it was a Windows Live Mail software issue.  They gave me the phone # to Microsoft.  Microsoft phone support said they couldn't help me and they said to do the online support.  Online support want to sign me up for a service contract  or they advised me to seek advice from this community online...so here I am.  Hopefully someone knows how to help!  Thanks in advance ....