WHAT download error?
A12... download & install error http://forums.adobe.com/thread/1289484
-more A12... discussion http://forums.adobe.com/thread/1045283?tstart=0
Error 46 may be caused by Comodo internet security
-Comodo may kill install https://forums.adobe.com/thread/1460361
What is the exact error code that you see?
-try some steps such as changing browsers and turning off your firewall
-also flush your browser cache so you are starting with a fresh browser
A chat session where an agent may remotely look inside your computer may help
Creative Cloud chat support (all Creative Cloud customer service issues)