[ic] Admin on 4.72 not working on catalogs built in 4.6.4

[Robert Trembath]

I brought a store built in 4.64 over to 4.7.2 and the customer side works
well with exception of getting a page expired message when I click on buy
now from a search result. Someone else today ran across this problem, is
there a fix?

Also when I try to login to the admin section all I get is an error message
produced by the3 process.html page. Please Help ASAP!
Many thanks,
Robert