Hey there, even when you uninstall SOF 2 it can still be sitting in your registry. Once you remove it from there and do a fresh install of SOF it should work for you. Try downloading CCleaner, search it on google. Once you have downloaded it, open it up and click "Registry" on the far left, then click "Scan for Issues"button at the bottom. Once it is done scanning click "Fix Selected Issues" button in the bottom right. If it asks you to backup registry just say "No" then click "Fix All Selected Issues" button then click OK.This might clean up left over SOF files for you, or might not. If it doesn't you have to do it manually.
Good luck!
Moon