I am using Avast5, and have been using "Avast" for the past 2 years This has been happening for about 1 week...also using Spybot which is usually off and unimmunizes, but to update and scan for logfiles and tracking cookies and repairs..I thought It was the problem so I uninstalled Spybot..Also I use Spywareblaster, Advanced System Care, Malwarebytes and Superanispyware for scanners...CCleaner, Eusing Registry repair, and Revo..Inernet Explorer 7 is set to default browser, but have Opera and Use Firefox with Noscript and Betterprivacy 99% of the time but to check email.....I click start.... Turn off computer .whether ...I click Restart or shutdown It goes to "Windows is shutting down" and STOPS ..I can wait for Hours and is still Shutting down...so I Hold the Power button to shut it down...Went to F2 and set all to default ...did scans with all Scanners Including Avast Boot scan ...Not even a Tracking cookie was found....Also Use a Password for Avast program access..And yes It is set to High on all shields cause it is my main protection...This I will try lowering down also...I Uninstalled the latest version2.30 of CCleaner cause it had issues with Firefox..so I got 2.29 version back...I checked my Taskmanager processes and tried shutting most down except idle,explorer, and Task manager...If I disable Avast until next restart, shutts down fine...and reBoots fine...Sorry for the lengthy Info but I tried almost everyting...open to any suggestions....Thanxs in advance for everyone's time.