Microsoft.com and any microsoft related site not working

Hello Team,

Since last 5-6 days i m having issue in some 2-3 systems, sometimes www.microsoft.com or any microsoft related site are not opening… This may cause due to some irregular activities in my pc…

I usually do, temp soln. as, open task manager, click on process, and End Process named LSASS.EXE NETWORK SERVICES and after this my issue gets resolved…

But team, please let me know permanent solution for this and also i use AVAST antivirus and Symantec antivirus.

Waiting for your reply

Thanks in advance
Vasim Memon