Help with microsoft office

[BlumerMooner]

I upgraded online from 2003 to 2010 microsoft office (wish I hadn't now). Little did I know that it was a thirty day trial. Now I cant open any of my files. How do I get my 2003 version back without having the original CD? I can't open any of my files? When I click on them I get message saying open with... ... then list, but none of them work.

Very frustrating. Any help would be appreciated.

Thanks