A customer told me about Windows 10 upgrade error: “CPU not supported”, but CPU is an Intel I5.
I have found this article:
http://answers.microsoft.com/en-us/windows/forum/windows_10-win_upgrade/cpu-not-supported/90fa67d1-71b4-4ac3-b46a-29563d3e3582
Substantially, run windows update with last updates, get

Windows 8.x  https://support.microsoft.com/en-us/kb/2976978
Windows 7 SP1 https://support.microsoft.com/en-us/kb/2952664

then re-run windows 10 upgrade. This should be fixed.

Other useful links are:
https://www.infopackets.com/news/9619/how-fix-cpu-not-compatible-windows-10-error
http://www.hwupgrade.it/forum/showthread.php?t=2731174
http://windows.microsoft.com/it-IT/windows-vista/Change-Data-Execution-Prevention-settings?86a92e20)