Hoping someone can help with this really frustrating problem setting permissions. I have read some of the permissions problems discussed in other threads but this is a bit different. I installed Windows 7 on two machines that were previously running XP Professional. Both installs were done to drives that had a lot of existing files and folders. As expected, the previous folders and files were seen as owned by a unknown SID (my old XP account) and under Windows 7 I had read-only access. Now the interesting thing here is that resetting permissions works on one computer but not the other. On the laptop system, I was able to easily reset all the old XP folders and files by running a command file script with these two commands to take ownership and assign permissions to my new Win7 account on all the root-level files and folders: takeown /f folder_name /r /d y icacls folder_name /grant my_account:F /t On the laptop, this worked beautifully. On each folder and file, it granted me ownership and then assigned full control to my Win7 account. Furthermore, the unknown SID also disappeared. On the desktop, the behavior is completely different! The "take ownership" command works fine, but the "icacls" command to grant permissions works only on individual files in the drive's root, not on folders. It absolutely refuses to grant rights to my Win7 account on folders or subfolders. The command reports success, and likewise trying to assign full rights for my account with Windows Explorer appears to succeed, but despite the apparent success the folder permissions remain unchanged!! My account appears in the ACL's but has zero permissions. Furthermore, on both files and folders, the old SID remains in place -- it doesn't disappear like it did on the laptop! The only significant difference I can think of between the systems is that the laptop is running the 32-bit version of Windows 7 and the desktop is 64-bit. Also, the desktop has two hard drives (behavior is the same on both). Not sure what is going on here but at this point I'm ready to swear that this is a bug in Windows 7 RTM! I just want to get this fixed so that I have ownership and permissions on my own files!!

Hi Wolfpup1, Before moving on, could you please check if take ownership works fine on the desktop computer? If it doesn't work, icacls command should not work. Also, please try to remove old SID first to test the issue. Hope it helps.