I want to install a new win7 on Vaio SVE1112M1E (came with Win8 pre-installed, and has Win10 installed now). In setup I've
- disabled SecureBoot
- set from AHCI to IDE
Vaio can't boot from external USB DVD (with win7 install disk). Every time I got "Operating system not found" error. I can't reach bootmenu (or setup) with Assist button or F11, I always got the same "Operating system not found" error.
If I plug a pendrive with Win10 install, Vaio boots automatically from pendrive, but Win10 install stops with "cannot install to GPT partition..." error when selecting target partition...which is normal for non-AHCI setting as GPT partition type is supported only in AHCI mode. The only problem that I can't reach setup with Assist button or F2 or F11 or Del, to re-enable AHCI.
For me it seems a catch-22 problem: non-AHCI setting prevents me from reaching the setup to re-enable AHCI.
I guess I may create a pendrive with Win7 install. Any other idea?
