Recently my Sony Vegas 6.0 started hanging on launch with 50% cpu usage (single thread at full load) on my dual core x2 4400+. Using Process XP, I discovered that apparently it hangs trying to modify the key HKLM\SOFTWARE\Sony Media Software\Vegas\6.0\File Format Cache\sctplug I wanted to delete the key and reinstall Vegas 6.0 but this key refuses to delete in registry editor. I tried everything from changing the permissions in the registry, try under different accounts (including the original owner), but this one is stubborn and simply will not delete. The error message I get when trying to delete the key is: "Error Deleting Key" [Window Title] "Cannot delete sctplug: Error while deleting key." It also throws error messages saying it cannot change the permissions on this key even though every account I try from (including the one under which Vegas was originally installed) is full Administrator account. I am able to delete all values under it and sub keys, but not this key. How do I delete this key?

Did you try in the safe mode? http://computervitals.com/

Disregard if this is how you edited the permissions... In regedit, highlight the key and get into permissions, then click advanced and edit the permissions of everyone to include delete. If there are subkeys, check the 'replace permissions on child' checkbox.

Ya, I tried safe mode. I did tried every possible combination of permissions including the one mentioned. Thats why I can't understand it. Is there a chance that the registry is corrupted at that point alone? If yes, how do I fix it? Any advanced registry tools (preferably from dos so that xp cannot block the deletion)?

YOu cannot do it from DOS. Unlike Windows 98, XP Registry uses hives in hierarchical arrangement. i_XpUser

Try typing the following into the run box: at 12:00am /interactive regedit.exe Change the time to one minute in the future. That should give you SYSTEM access and you may have better luck deleting the key.

Warning: The AT command is a powerful command line tool that can corrupt your registry outright. If you are not thoroughly familiar with it...... i_XpUser