need to put Home Premium 32bit on a computer

Hello all, I am trying to fix another computer and I had a Windows installation disk, but it turns out it was for Ultimate, and I only have the COA for Home Premium and also everytime I try to use this computer it keeps giving me the blue screen, the laptop is the Toshiba satellite L455D-S5976, what should I do to get my copy of Windows genuine without having to pay for it, is there any way that I can easily take off Ultimate and put Home Premium on it, so it works again, thank you in advance

You can use this tutorial to put the correct licensed version back on the computer,

Clean Reinstall - Factory OEM Windows 7

Links for the official installers are in step 1.

ok I am doing this using a flash drive and the Windows 7 USB/DVD Download tool is not reading my flash drive and I have no blank DVD's what should I do

See if trying option two of this tutorial helps,

USB Windows 7 Installation Key Drive - Create

You might want to use an older version of imgburn that doesn't come with the garbage the newer one does.

Discuss : OpenCandy in ImgBurn

What always works for me when others fail is UltraISO Software To Create Bootable USB Flash Drive.

Be sure to delete all partitions during the booted Custom install, using the Drive Options shown in Steps 7 and 8 of Clean Install Windows 7.

As suggested if you follow the steps in Clean Reinstall - Factory OEM Windows 7 you'll get and keep a perfect install.