Q: Updating from OSX Lion to Yosemite failed

Hey,

I've ran into a problem where i thought my MB Pro '11 (with Yosemite installed) was officially dead. The computer was in sleep mode and when i tried to log in, it just crashed and shut down completely. Tried to reboot it and on the signing in process it just keeps on loading and nothing happens until it just shuts down itself.

I thought the problem was the hard drive and I erased it completely and downloaded the OSX Lion 10.7.5.

Lion runs smoothly but the problem is that i can't update to Yosemite anymore.. Tried repartition of the hard drive and it didn't help. App store lets you download the software but in the end of the download it just says can't download this software.. I thought that I needed to download earlier version of the OSX but the same thing happened.

Any tips and tricks I haven't tried that could work?

Thanks!