47843 simple oscommerce fix

hello i had oscommerce working fine...then i tried to install a verisign payflow contribution upon completion i noticed that everytime i add product to my cart then go to checkout the product disappears. I backed up everything and uninstalled the contribution but still can't get it to work. I'm sure it's something easy i'm just not incredibly good at php. Also in the past i installed a guest account contribution too fyi. Thanks.