Toshiba repair error

[Sasa_1982]

Hi. I bought a toshiba c50b-14z laptop with windows 8.1. I want to istall windows 7 for that. I delete the partition, and I format it, but that type of windows don't like that kind of partition (GPT or somthing like that). I want to do the factory reset, and it's not working. I tried everything to restore the original OS, but it's not find the drive. I didn't touch the system and recovery partitions. I don't have more idea, how can I fix it!
Somebody can help me?
Thanks in advance.

 

[ffg7]

have to change in the bios from uefi to sata for the hard drive for the win7 format to work. done ot a few times but not enough to be certain it is sata or something else.
win7 drivers link. http://www.toshiba.co.uk/innovation/download_drivers_bios.jsp?service=UK

 

[Sasa_1982]

I have only UEFI and CSM. The installation (what is not working) and the repair (what is also not working) starts only in CSM mode,
I only found one SATA switcher: Perfomance mode and power saver (I'm not sure on the last one).

 

[ffg7]

read this link as you need to select csm. https://aps2.toshiba-tro.de/kb0/TSB2B03F30002R01.htm

 

[Sasa_1982]

If I want to boot from disk, I do the same (above), but the win8 show me an error: you can't install this OS to this partition 1, and 2, 3, 4, 5, 'cause it is GPT partition.

 

[ffg7]

have to delete those partitions, make new partition(s) then format the partition(s) after booting up on your win7 disk.