Friday, November 16, 2012 9:12 PM
I am only able to open, and view thumbnails, for a maximum of 6 RDP sessions on my Server 2012 box at a time in Remote Desktop Connection Manager (RDCM). If I add more sessions I just get a variety of connection errors for the additional sessions. If I activate a 7th session one of the existing 6 sessions goes off-line with a connection error message. Sometimes the error says 3334, sometimes the error says 0x8345000E, and sometimes it just says there is a connection error.
I have checked Group Policy on the server to ensure I don't have any settings restricting the number of RDP sessions.
In fact, I will often have 30 or 40 RDP simultaneous sessions opened, I am just not able to view them all in RDCM. I have seen reviews of RDCM with screenshots showing dozens of thumbnails so it seems to be something that's possible to do.
Are there any settings I should make on the server to allow RDCM to connect to more than 6 simultaneous RDP sessions?
Just to be clear, all these RDP sessions are running on the same server. Also, I am just using the trial license for Server 2012 and Remote Desktop Services right now. I don't think that should have an impact, but I wanted to be thorough.
Saturday, November 17, 2012 2:49 PM
I also use the Remote Desktop Connection Manager version 2.2 to RDP into my server. I do not have any issue opening more connections than the six you mention. There might be some other reason it is not working properly, but I believe it is not related to RDCM
regards Robert Maijen
Saturday, November 17, 2012 7:53 PM
Are there some settings I need to make on Server 2012 to allow more than 6 RDP sessions? I can easily run up to 50 simultaneous sessions (I haven't tried more), but I just can't view them all in RDCM. I have checked Remote Desktop Group Policy settings to ensure that no limits were in place.
Is there something else I should check?
Curiously, RDCM will actually connect to ALL my RDP sessions when I start it, but then it starts disconnecting from one session after another until only 6 active thumbnails are visible. The other RDP sessions are still running, they just aren't visible through RDCM.
Sunday, November 18, 2012 10:16 AM
So it is not just RDCM that cannot connect but sessions are created but disconnected. Do you have GPO's applied for idle time?
regards Robert Maijen
Sunday, November 18, 2012 8:33 PM
It is just RDCM that seems to have a problem connecting to more than 6 sessions at a time. I have been able to open over 30 RDP sessions within a single RDP session (putting them all in mini windows) without any problem.I
I do notice a lot of event ID 1104 ("The client failed to establish the multi-transport connection.") and event ID 1026 ("RDP ClientActiveX has been disconnected (Reason= 3334)") messages in the event viewer when I try and open up lots of simultaneous sessions with RDCM.
I have left the GPO settings for idle not unconfigured.
I was thinking that maybe this could have been an issue with using NIC teams, so I deleting my NIC team and am just using a single NIC now, but that hasn't helped.
Monday, November 19, 2012 5:17 PMTo give an update: I have disabled RemoteFX, lowered the color depth, and turned off compression in Group Policy. None of these tweaks have resolve the issue though. I still can only open 6 (or sometimes 7 or 8) simultaneous thumbnails in RDCM.
Tuesday, November 20, 2012 2:15 AMI have solved the problem! After a lot of dead ends I finally found that I could get as many thumb-nails working as I like with RDCM by setting Network DTC access to not require authentication under Component Services. You can access component services on Server 2012 using this command: dcomcnfg
That said, I have found that it is just too slow to have more than 20 thumbnails running at a time. The refreshes are just too slow and bog RDCM down. However, having 20 thumbnails is a far sight better than the 6 I have been limited too!
- Marked As Answer by TP MVP, Moderator Tuesday, November 20, 2012 2:36 AM