Dell XT2 tablet running Win7 Ultimate x86, with a Bitlocker-encyrpted 256 GB Samsung SSD. We've seen this on two tablets, one of which had its SSD replaced. At random times, with no user action, the TPM becomes disabled in BIOS. There are no symptoms of this until the user reboots, when he receives the expected complaint from Bitlocker. He can then go into the BIOS and turn the TPM back on, after which everything works as expected until the next time it happens. Dell tech support seems totally mystified by this, although they believe the TPM is becoming disabled in response to data corruption on the drive. They suggested upgrading the drive firmware, but it's already at the current version, as are all drivers, BIOS, etc. There have been other signs of data corruption - for example it will randomly run chkdsk at startup a couple of times a week. I turned off Bitlocker and decrypted the drive, and the problems have apparently stopped. That includes chkdsk, which the user reports would run occasionally with Bitlocker disabled, but has not run since I decrypted. I can't find any information about this, and we run Bitlocker trouble-free on other systems with mechanical hard drives, so I'm reluctant to blame Bitlocker - but wondering if it could be something to do with that SSD or some kind of combination effect. Thanks! Dave Nickason - SBS MVP

Hi, Thanks for posting in Microsoft TechNet forums. As no obvious relation, I suggest narrow down the issue. First, please prepare clean boot to check if certain software conflict. Meanwhile, please manually try SFC and complete a scan. Best Regards Magon Liu TechNet Subscriber Support in forum. If you have any feedback on our support, please contact tngfb@microsoft.com Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi Magon, thanks for responding. As far as the clean boot, Dell sent a new SSD containing their standard OEM image. We added one application every two or three days, and did not run into the problem until we enabled BitLocker and encrypted the drive. SFC doesn't find any problems. The difficulty in doing clean boot is that there's no reliable way to cause the corruption. So, we could clean boot and it could run fine for days, or it could fail at any point. But in the interest of usability, I currently have the drive decrypted. I don't expect to see any issues until I re-encrypt it, either with clean boot or otherwise. I've done a lot of the basic troubleshooting, and Dell is still trying to figure out a possible cause for data corruption on their end - looking for Intel storage drivers, SSD firmware, etc. I think my best shot is if I can find someone who has seen something like this before.Dave Nickason - SBS MVP

Hi, I have read one post that indicate conflict with audio card driver. You can try Safe Mode to test. Start your computer in safe mode http://windows.microsoft.com/en-US/windows-vista/Start-your-computer-in-safe-mode Regards,Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Dell now believes this to be data corruption caused by a faulty RAM module. They've apparently had enough instances of problems that they've traced it to a particular batch of RAM. They are sending a replacement, after which I will re-enable Bitlocker to test and hope for the best. Interesting that we only saw symptoms of corruption while the drive was encrypted (but regardless of whether Bitlocker was enabled or not). Decrypting the drive immediately eliminated all symptoms of corruption. On the off chance this does not fix it, I'll post back on this thread (based on experience, it'll take 2-4 weeks for symptoms to start again if it's not fixed). Thanks for your help, Magon.Dave Nickason - SBS MVP

Dell now believes this to be data corruption caused by a faulty RAM module. They've apparently had enough instances of problems that they've traced it to a particular batch of RAM. They are sending a replacement, after which I will re-enable Bitlocker to test and hope for the best. Thanks for updating us the current situation. Your time and effort is appreciated. For the time being, since Dell has give their explaination, I will mark this as answer. After 2-4 weeks, you are welcomed to post the result or further inquiry here. Regards,Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.