Permissions and TrustedInstaller

Let me explain my problem in as simple as i can. I have a desktop PC with 4 partitions. Earlier i was using Windows XP on C drive, later installed Vista RC1 on D Drive. yes, it was Dual Boot. Now i have uninstalled XP and installed Vista RTM to C Drive. So i have Vista RTM on C and RC1 on D.

Now i want to remove Vista RC1 from D partition. To do the same, i simply deleted all folders in D drive except Program Files, ProgramData and Windows because these files are not deletable. Whenever i try removing them it gives me an error message saying "You need permission to perform this action". I dont want to right click the drive and format becais eit contains few important data folders as well. I also changing ownership to admin group, as well as give full rights to admin group to these folders but no help.

Furthermore i also changed the owner of a folder from TrustedInstaller to admin. Due to some reasons i now need to set TrustedInstalled back to the owner, but I can't find it when using "Select users and groups". Hence i need you guys helps regarding these two stuffs.

First please let me know how can i delete those undeletable folders from my D drive? and secondly what is the correct location of TrustedInstalled ?

Please help.

Hey Bob, did you tried changing ownership to your user account, not just the admin group? If not, try it and ensure you check the box to propagate to objects and subcontainers. It should work fine.

Thanks for the help LeonL. I tried changing the ownership to me, but that dint helped me either. It still gives me the same error message every time i try to remove the folders saying "You need permission to perform this action."

Damn.. any other suggestion please?

Run a command prompt as administrator (right click CMD, choose "run as administrator"), delete the folders from the prompt.