I'm getting extremely long delays (10~30 seconds) in SQL Server Management Studio 2014 when attempting to connect to a SQL Server 2012 instance over TCP using Windows Authentication. This happens when connecting Object Explorer or a new blank query window. Once connected, running queries is fast. The problem does not happen when I connect using SQL Server authentication.

Environment:

• Windows 7, logged in as a domain user
• TCP connection via IP address (not hostname)
• The server is at a remote location connected via VPN
• No encryption

When I logged into a co-worker's Windows 7 computer with my domain account, and connected to the same SQL Server through the same VPN, there was no delay. When the same co-worker logged into my PC with his own domain account, he experienced the delay. These tests show that the problem is unique to my PC.

Things I've tried with no success:

• Disabled anti-virus and firewall
• Renamed the "12.0" folder under "%userprofile%\AppData\Roaming\Microsoft\SQL Server Management Studio" to "_12.0" to force SSMS to recreate my user settings.
• Force Network protocol to TCP rather than <default>. I also tried Named Pipes but my server isn't setup for that.
• Installed SSMS 2012 and tried that instead of 2014.
• Disabled IPv6
• Blackholed crl.microsoft.com to 127.0.0.1 in my etc\hosts file.

TCPView clues:

• Using TCPView, I noticed that when I make a new connection, its state becomes ESTABLISHED right away, but then one or two more connections with the SQL Server are continually attempted and closed with TIME_WAIT. On my co-worker's computer, these connections are ESTABLISHED and solid. So I'm pretty sure this is the source of the timeouts, but what are the connections for, and why do they fail? (I don't have any addons in my SSMS.)

Any ideas?

I was about to uninstall all SQL Server related apps from my PC and reinstall, but there are dozens of them in Control Panel > Programs and Features, and I wanted to avoid the hassle since there is no guarantee it will help...