Hi forum, I hope you're having a good day. Please help me with this situation of mine. Summary: The system requires chkdsk for the 2 mechanical hard drives in RAID-1. The disk check has returned lots of "Replacing invalid security id with default security id for file" ... Why is this happening and should I be concerned? Details: My hard drive setup is 1 SSD (Corsair P128) and 2 RAID-1 mechanical drives. Previously, in my BIOS, the SATA mode was RAID. Then my Windows 7 x64 Pro on the SSD got corrupted. I tried fixing it but I wasn't successful so I decided on a re-installation. I updated the SSD's firmware which wiped the SSD cleaned. In order to do this, I had to set my BIOS SATA mode to IDE. Then I installed Windows 7 x64 Professional to it. Then I changed my SATA mode to AHCI (this is recommended by Corsair). I booted normally into Windows several times. My RAIDed data seemed to be there, intact. Then, following an advice on the Corsair forum, I relocated the user variables and system variables to my RAIDed disks. These settings can be accessed using: Control Panel >> System Security >> System >> Advanced System Settings (on the left panel) >> Advanced tab >> Environmental Variables... Specifically, I changed the user variables TEMP and TMP from their default values to D:\Temp\ (D being the letter assigned to the RAIDed configuration). I also changed the system variables TEMP and TMP from their default values to D:\Temp\. The Corsair guide also recommended relocation of the page file but I didn't do that step. The guide can be found here: Windows 7 Tips & Tweaks - The Corsair Support Forums After this change, I restarted my system several times while installing drivers. Everything seemed normal. Then I installed Intel RAID Manager. The installation required me to restart so I did. After the first restart, I logged into Windows and I was asked to restart again. During this 2nd restart, the system asked for chkdsk for the RAIDed disks and I authorized it. I didn't look at this disk checking and went I returned the system already booted into Windows. I logged in, and tried to access a folder on D (again D is the letter for my RAID 1). I was told I need to give a permanent authorization in order to access the folder. I did that and was able to get in the folder. I didn't try to access any subfolder or any file. In fact, I just restarted the system. After this 3rd restart, the system asked me for another chkdsk on the RAIDed disks. This time I watched the process and it's been returning "Replacing Invalid Security Id with Default Security Id for file" n, n+1, n+2, ... It's been doing this for more than an hour now. Why is the situation happening? Is there something wrong with my physical hard drives or my Windows? If so, what should I do? Thanks a lot. UPDATE: After a while (~2 hours), the chkdsk finished. I was able to log in to my account. But I had to give permission to gain access to folders in drive D. After the permissions, the subfolders and files seemed present and accessible. I was able to listen to some mp3s and watched some picture slide show. Nonetheless, everytime I right clicked the drive D and chose Properties, I get the following message: The Recycle Bin on drive D:\ is corrupted. Do you want to empty the Recycle Bin for this drive? I'm afraid to restart my machine again. Something not normal is going on. I'm backing up my data to another drive. As in, I'm manually Ctrl C , Ctrl V my data to a USB drive. I dont' know if it's too late, as Windows has probably corrupted all of my files on this drive.I don't know what my next move after backing up should be. Please help!