As far as I know no one has reported problems upgrading the firmware to date. That said there is always a chance something could go wrong in the upgrade process, so it is always advisable to back up before hand.
What you describe however sounds like a driver problem that is preventing Windows from booting. Did you by any chance change from AHCI to IDE mode to install the firmware update and then not reset the bios to AHCI mode afterwards?
Hi, No I didnt change the bios settings. It was by default in AHCI mode and remained so after update.
I cannot boot via safe mode either as it blue screens while loading also.
However, I can get Startup Repair to work. After scanning it says it cant repair the problem automatically however there are problem details:
Problem Event Name: StartupRepairOffline
Problem Signature01: 6.1.7600.16385
Problem Signature02: 6.1.7600.16385
Problem Signature03: unknown
Problem Signature04 21200973
Problem Signature05 AutoFailover
Problem Signature06 4
Problem Signature07 BadDriver
OS Version: 6.1.7600.2.0.0.256.1
Local ID: 1033