I try to upgrade win7 build 7067 to latest 7077 and after a few restart, windows boot stops right before it enters logon screen. I try every possible way of instalation- from virtual cdrom, from DVDrom, from directory on hard disk, but everytime it stops at same moment in last reboot, after the system must load. After black screen with animated coloured windows, a blue screen show up for a second and then computer restart. Restart boot gives me option to revert windows to previous version and after restoring the previous version in the desktop shows up a message that windows update was not successfull. How can I upgrade to 7077, because i don't want lose all my previous setups, which takes too much time?