My computer changed from 64 bit to 32 bit?

My computer changed from 64 bit to 32 bit?

Added (1). I have a Lenovo G580 and here are the specs:
My computer changed from 64 bit to 32 bit

The other day I went to the shop because I needed my laptop repaired (It wouldn't go past the lenovo screen after I powered the computer on) . Surprisingly the one time I turned it on there, it worked but I decided to let them repair it anyway. When I got it back, it had windows 7 professional instead of my previous windows 8.1 and it changed from 64 bit to 32 bit. They formatted my computer. What caused the 32bit change?

rohan

When the OS was loaded it was loaded in the 32bit format, you should have your install or recovery media from your first install of the laptop where you can revert back to the system W 8.1 and 64bit if you say that they have formatted your system then it is just the OS which is there and you have lost all your files any way so reinstalling your OS is probably the way to go. I would have thought the store would have either asked you about the files and data on the system before they wiped it

nikkai

They were not a good repair shop if that happened and I would go back to them to get them to explain what they have done without consulting you.
What repair did they actually do because your hard disc shout have recovery software installed on it which will reinstall your operating system and revert your p.c to the same as when you bought it.
As someone has already said did you loose any personal data from the repair

Norm F