I've struggled the same problem before and now again but with my 8.1 and would say that the problem discussed here is not so complicated as described. My OS is Windows Embedded 8.1 Industry Enterprise. Everything with the system before the Microsoft's March Update was perfect (underline)! I use F-Secure Internet Security 2014. After the windows update couple of days ago and a consequent system restart my system went to a BSOD with a CRITICAL_PROCESS_DIED message as a first non-black screen. It didn't allow me to do anything - no restore, no back to a last working condition, just restarted and stopped at black screen with blinking white cursor. And again. I forcefully shut the PC down and started it again and yet went into the interactive repair screen where I managed to restore the system to an earlier date restore point. So far so good, I repeated the full update and result was the same - negative. Restored again and figured out that my hosts file was cleared and written in it that it was "infected" (shortly said). Some of the programs were with expired trial period. I restored the hosts file with a saved in advance copy of it. Updated again without KB2929961, KB2930275 and Windows Malicious Software Removal Tool. At last, it was O.K. I manually fixed the expired progs and restarted successfully. Deleted all my previous restore points, cleaned the system up, defragmented it and created a new restore point. Restarted successfully. Next, I applied KB2929961 and KB2930275 only. This time restart was successful. I applied Windows Malicious Software Removal Tool - no success. Restored to an earlier point - hosts file was wiped up again. Restored it. Restarted successfully.

Now, I'm wondering which bank should I rob to have enough money to buy all needed software or to continue fighting/hiding game with you Microsoft, Mac, Adobe, Corel etc., every month. I think you got me.