Windows 2008 R2 SP1 hosting NPM/NTA, SQL 2014 on separate server. SAM upgrade to 12 went fine. NPM upgrade to 12 went fine. NTA 4.2, not so much. Can't get NTA to connect to the SQL server. I've gone so far as to completely remove NPM & NTA and do a fresh reinstall making a new database as well. I cant get past the NTA server connecting to the NTA database. The connectivity is there but it just wont connect. No firewalls in place, AV completely disabled, checked and double checked SQL accounts. I've attached a screen shot. It stays like this for about half a hour before it times out.
At least in my case, after working with support, and uninstalling Symantec Endpoint Protection on both the NTA/NPM server and the database server they finally connected immediately. Disabling SEP didn't work. Only after a complete uninstall did it work. Obviously not acceptable, but sharing for others.