Am i screwed?

Well, I just bought a 40gig ps3 from a guy who found from craigslist. He didn't give me anything like warranty or proof of purchase. I didn't think it was that big deal at the time. Ps3 seems to be working fine except for that it won't update.
So currently it's on version 2.36. Everytime when i try to run the update via USB or internet, it gives errors. I've been googling past few days to find some sort of solution to this, but it's kind of ending up that i have to send the ps3 to sony which i don't think is gonna happen cuz i'm not the original buyer from the store. I tried to contact the guy who sold me this, but he wouldn't get back to me so the question is am i kind of scewed now?

Dang it, i shouldve just bought it from the store......

If you could share your knowledge/experience (sharing is caring.. ;) ) and help me get through this, i'd really really appreciate it!

Thanks for reading...

oh the errors i get are: The data is corrupted, error : 8002F997 (shows this one when try it via internet)

or error 80029564 (shows this one when try it via USB)

I've also tried the update after formatting and setting it to the defaults and restoring the system and stuff so...yea...im there..

try formatting you mem stick [ntfs i believe google it to be sure] and using a different usb port,plug it in after the ps3 boots up all the way

try to copy it from the thumb drive before updating

if your using wireless try a wired connection if possible,

try restoring your ps3's default settings before updating,

if all else fails try reformatting the ps3 hard drive [in the settings somwhere] then the update

i found all this info through a google search.havent tried any of it so do it at your own risk.

worst comes to worst call sony give the error number and ask them.