DS 6.9 Remote control stopped working.
Server: DS 6.9 (517) SP5 on Windows Server 2008 R2 x64 Std. SP1
Clients: DAgent 6.9.517 (64 Bit) on Windows 7 pro 6.1.7601 SP1
Problem: DS Remote control won't connect. The RC window stalls on a completely white page with "Waiting for client to accept connection" message, and then eventually times out with "unable to make an image thread connection to the remote machine" error message. Same problem on all clients.
I don't use the DS Remote control feature daily so I just discovered one day that it no longer worked. I scoured the forums for any help I could find and threw every configuration switch that was suggested on both the server side and the DAgent client side, booting and rebooting for a day and a half trying to find where it was broke. Then, I decided,maybe it was a MS update to the server that caused the problem days ago. I removed the 7 most recent MS updates from 2/27/2013. After a reboot, RC started working again. I then started adding them back one-at-a-time to find the offending update. After each one was installed and a reboot, RC continued to work. Now they are all back in and RC still works.
I don't think this is a fix because I still can't explain it; maybe the updates were installed in a different order this time or something. I just thought I'd post it here because it may help someone else who is experiencing the same problem save a day and a half of searching.