OK this is doing my head in. I don't know whether it's a hardware or software issue. I can only think of a few things it could be. Basically A few months back I upgraded from 2GB of memory to 6GB of DDR2 and then to 8GB a couple of weeks later. I also changed from Win7 32 to 64 to take advantage of it. I installed Win7 64 on a brand new Samsung F3 1TB drive (Although I can't recall in which order. The memory or the hard disk). Ever since then I have had issues with BSOD's out of nowhere. I Swapped out the first 4GB with Crucial and again last month I swapped the other 4GB with them. Things seemed stable again for a week or more until last week when I went away to stay with my parents and did some remote desktop stuff. I ended up coming back home to see why I could not connect and found it sitting at a bootup repair screen with a failed repair. Also system restore said there were no restore points (There was when I left it! Where did they go?). The error was unknown and booting up with autostart turned off was not very helpfull either (I can't recall the first BSOD and to be honest. I was in a rush to get it fixed because my father was with me and waiting to leave). So I yanked 2x2GB sticks of memory out, set the voltage a little higher and reinstalled a basic Win7 setup, then left. Doing some remote desktop work I reinstalled some stuff and did a check with HD Tune which showed a warning on the drive about Ultra DMA CRC Count of 7 under the data column. Googling I found out it can be caused by a bad cable. I planned to change the cable when I got back home. I also ran a sector test which passed with no bad sectors. I got back Wednesday, changed the cable and reinstalled all my apps and settings and all seemed fine. I even put the other 2x2GB sticks back in. That is until Friday morning. I got up to find it was again at the startup repair screen saying it failed to repair whatever the problem was. Again system restore said there were no restore points when there definitely should have been. This time it showed a problem with ntdll.dll as being corrupt and unfixable. I tried doing a chkdsk and even manually copying the file over but it did no good. It still BSOD'd on me so I switched off auto restart and looked at what the BSOD was saying. The BSOD message showed SYSTEM_LICENCE_VIOLATION 09. I kinda understand that one but I had not even tried to run a loader or anything. It was still in trial mode state. So I have had to reinstall again! I have taken 2x2GB sticks out again just in case and I have ordered another hard disk because of the suspicious message in HD Tune. I'm kinda pulling my hair out here wondering if it's going to do it again. I can understand BSOD's. But to just suddenly go to a state where it will not boot and is irreperable and losing system restore points is odd. I can only find one correllation between these last two uncorrectable events. I installed a Win7 firewall helper tool which lets you block or allow programs using the Windows firewall. Is it possible that this blocked activation components from phoning home and thus rendered the system as a bad activation and so put it into an unlicensed state (The system licence violation message thing?)? Or am I looking at a hardware issue here? HDD? Memory? Motherboard? Specs as follows. Win7 64 Ultimate Asus P5N-E SLI motherboard with latest SLIC BIOS 8GB Crucial DDR2 800 (But currently only running 2x2GB sticks). Samsung F3 7200RPM drive Intel E6600 CPU (Not overclocked) I also am having trouble finding out what the voltage for the memory SHOULD be set at. Especially when running the full 8GB which may be putting a strain on the motherboard chipset for all I know. I hear the P5N-E SLI is a twitchy mobo at the best of times. Any advice greatly appreciated.