Problem similar to this one only with SQL Server 2012. None of the suggested registry edits have worked. This problem was supposed to have been fixed back in 2008 SP1.
Here's the sequence of operations:
Several years ago: SQL Server 2008R2 Express edition was installed on workstation along with SSMS.
Recently SQL Server 2012 Enterprise Trial was installed on the workstation, along with SSMS2012.
The trial expired. A license for SQL Server 2012 was acquired and the 2012e was installed on a LAN server with the product key. Success there.
Back on the workstation, first I attempted to downgrade to a free edition. Downgrade succeeded but SSMS2012 kept saying the trial had expired.
On workstation, then I attempted to use Edition upgrade to Standard (licensed) version. Edition Upgrade succeeded but SSMS2012 kept saying the trial had expired.
Reinstalled SSMS2012 on workstation using the binary image of the licensed (paid) version. No joy. Same error.
I'm using freeware TOAD for SQL Server in the interim but would like to have SSMS since the freeware version of TOAD has needed features disabled and I would rather not ask for more money to buy a replacement for something we have already paid Microsoft for.
If you've found how to fix this problem for 2012 please advise. Thanks