urls requiring file saves registry edit

i did this earlier, several URL's i frequent ask for me to save a file or open it... i found a registry edit somewhere that stopped that but i had to do a full reset and though i thought i had it backed up, i evidently did NOT!!! $@#$@#@ and now i can't find it anywhere here! i think i got it from this forum's tech pages...

if you can point me in the right direction?

thanks!

What would one of said URLs be? Sounds like a MIME issue.