blue screen at startup.

[resand]

My Lenovo desktop locked up and I rebooted. First it went in to an endless reboot and after several tries I got the Lenovo start screen and then a blank BLUE SCREEN. The mouse and keyboard work. I updated to 10/10.1 over the net, no disk. I am hoping someone can help.

 

[WinOutreach2]

Most BSOD include an error code that can help to identify the cause of the crash. A blue screen could be cause by a wide number of factors. Some of the more likely causes include driver incompatibility, boot file corruption, and third party software that launches at boot. You report that you are experiencing the crash very early in the boot sequence, so boot file corruption and driver issues are most likely.

You will need to create installation or recovery media to perform further analysis or recovery of your system, as you are unable to access a boot environment. From a USB Recovery Drive you could attempt to use BootRec /RebuildBCD as detailed here at Microsoft Support.