I have a Dell M6400 (BIOS A09) that was happily running Win 7 Ultimate until the most recent updates. After a ton of reading here, I think that I've learned enough to ask intelligently for help. (And I'll gladly read more if someone can point me.) Thanks in advance for your expert insight. My machine was shipped with Vista (and an XP downgrade) and I installed the Dell OEM "auto-activation" Win 7 Ultimate on it. I believe that the problem is that my SLIC certificate (in the BIOS?) somehow says that I'm only allowed to run Vista and not 7. Does that sound right? I've DLed SLIC ToolKit 3.2 to see what I can learn, but it doesn't seem to tell me any licesning details. Can someone please help me understand what I need to do to update my BIOS or SLIC table to happily like Win 7 again? I'm betting that it is a simple few byte update somewhere if I just knew how and where. I'm also slightly scared to brick my machine (as it is my only real PC here), so I'm treading very cautiously and asking for help before I do anything stupid. Thanks in advance for your help.