Hi, frequently (but not always) when I shut down I get an error message where windows is trying to close ccsvchst.exe (which seems to belong to Norton) but cannot.At this point it seems I have to run chkdsk just before logoff and that does seem to help and help prevent problems at login (but I'm not sure that my problems at login are related to ccsvchost).I scanned all my folders containing programs related to svchost --including Prefetch, System32, and Microsoft.NET/Framework and alo scanned System, downloads, and addins with a Norton scan but Norton found nothing amiss.\I did find the thread:http://social.answers.microsoft.com/Forums/en-US/xpperformance/thread/d022cae7-0304-463c-a9d and maybe I do have a virus but my svchost program does not seem to use memory excessively though the file in prefetch has been recently modified (just before the trouble started); the big user of memory for my pc is IE8 (ccsvchst.exe is close behind but it does not increase memory usage) so mine is a different problem What has given me trouble logging into user accounts (I have Windows XP; I've updated; I just checked my hard drive and it's fine just past 1 year since I bought it I only connect to the internet in non-administrative mode except to do updates . . . I do use a wireless but long ago disabled file & printer sharing, peer-to-peer too; and after this problem disabled data execution for all. My Norton just expired and I could not renew right away although my online backup did renew so I do and do not have antivirus software)Thanks!Best, --C. E. W. 1 person needs an answerI do too