Class Not Registered Error Prevents Device Manager from Opening

I am using Vista from some last couple of months. It looks to be working fine, but in few days I am getting errors on it. I did not new changes. I am looking for some video edition software. So I test a number of trail tool. Now from last couple of months I am facing problem related to Device Manager. Whenever I open it I am getting a error that Class Not Registered. I am sure this problem does not appear because of those small edition tools. There some other fault. Is anyone having the same problem. What can I do to fix this.

Try using devmgmt.msc. Type this in Run box and hit enter. If it popup the same same error then it looks some kind of internal file corruption. It looks there some registry problem in your system. Try to run system restore and then check back. If system restore does not work then you might need install some registry cleaner software. There can be virus also. Check your system properly.