I'm trying to install Windows 7 Ultimate over my existing Windows 7 Professional. I downloaded the ISO from Microsoft and burned the install disc at the slowest speed possible (x3).
I booted to the DVD, but at the second screen I am already getting an error! That screen I am choosing between "Upgrade" and "Custom". I am trying to choose "Custom" but then I get the error:
Windows installation encountered an unexpected error. Verify that the installation sources are accessible, and restart the installation.
Error code: 0xE0000100