For the last month I have had a major mind bending issue with my system going to a hard lock on the OS and either losing all functionality (no mouse or keyboard functions) or can move mouse but just keep having an activity wheel and nothing responds. The only solution was to restart or hard power off. This turned into a massive learning curve and after many hours (greater than 30) of system analysis I think I have finally isolated the issue. This was occurring at anytime (could be morning or night) and during any activities (gaming to web browsing to File Explorer, etc). It was observed that the SSD (Primary Boot) was at 100% when this occurred. That is after about the 20th crash I first noted the HDD activity light on the case was staying constant. Next I opened Task Manager and noted the SSD was at 100% and staying there. Event Viewer shows that I have 50 Critical events since 22/10/2016. These coincide with my system OS locks. They are all: Kernel-Power 41 (63); Reviewing the information flags before this event I found a driver that seems to be casual and after analyising the Windows System logs for the date/time stamps for the Critical Events I keep seeing: EnhancedStorage-EhStorTcgDrv Event ID: 12 or 100 Click to view full size! Googling EnhancedStorage-EhStorTcgDrv a common theme started to appear: A lot of Micron Crucial SSD owners (they top the google search results) were experiencing this issue across many models of their SSD range. As my system has a Crucial M550 I also feel into this category. Issue: With Win10 my system was just using "Windows generic storage driver" for the IDE ATA/ATAPI controllers. Going to my mobo (Asrock z68 extreme4) website for Win10 drivers it only offered 3 and none of those were for for SATA/AHCI drivers and previously this system had worked fine with a different make of SSD for the last ~4 years without issue. Last night I went back and found the Marvell and Intel (RAID) SATA/ACHI chipset drivers, and although they were only listed upto Win7 OS I installed one (the Marvel as it was a exe) and then updated the other via Device Manager and have not had a system lock since (touch wood). In summary: from the forum posts I was reading it has to do with Win10 encryption (Bitlocker) wanting to over-ride the Crucial SSD Host Controller (HC) instructions. http://forum.crucial.com/t5/Crucial...TCG-Command-has-returned-an-error/td-p/149506 I hypothesise that Win10 was providing the generic Standard SATA AHCI controller drivers - this was allowing Win10 to override the mobo chipset and then the Micron SSD Host Controller and causing the system lockups. By installing the mobo storage controllers - even though they had last been published for Win7 - it allowed the mobo chipset to control the storage drivers and not conflict with the Micron SSD HC. So far stability had persisted (3 days later). Edit: it has now been a week and this issue has not re-occurred.