Long story short. New install of Windows 7 Enterprise (90 day trial) 2 days ago onto new PC. PC wouldn't boot tonight and removed CMOS battery to sort it. Didn't reset date (was 2002). Booted Windows. It gets all upset and says my install has expired and I need to activate it. Then, won't let me activate, says there's a security issue. Won't let me buy a key because it's not released it etc. Any ideas?