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Grey Screen

VncUser2014
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Re: Grey Screen

Post by VncUser2014 »

Do we need to update the server or also viewer with your new download? I haven't checked the contents yet.
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Rudi De Vos
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Re: Grey Screen

Post by Rudi De Vos »

zip only contain the winvnc.exe, no viewer changes were made.
VncUser2014
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Re: Grey Screen

Post by VncUser2014 »

We just did the test on Win7 x64, the problem seems fixed! Thanks a lot, if other testers have the same good results, will you provide a new official version?
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Rudi De Vos
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Re: Grey Screen

Post by Rudi De Vos »

That's good news...let's hope it also fix the grey issue for other people.

Other updates are also in the source, need to check what changed and all need to be proper tested before release.
UsernameIssues
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Re: Grey Screen

Post by UsernameIssues »

Rudi De Vos wrote:That's good news...let's hope it also fix the grey issue for other people........
It seems to have fixed it for me too. I tested the version in your zipped file on more that 30 live/real computers and on two Virtual computers (a mixture of W7 64bit, W7 32bit and XP 32bit).

Thanks for your time on this.



Normally, I would start new threads for the next issues that I'm going to mention, but I want those reading this to know that I am testing with the viewer from 1.2.1.1 and the server binary from the ZIP file posted earlier in this thread. https://forum.ultravnc.net/viewtopic.ph ... 07#p100628


1) Status windows:
My testing of the grey screen issue involved opening several VNC sessions in rapid succession. I noticed that a window with the title of "VNC Viewer Status for [IP address]" opened (and stayed open) for some of those sessions. Some of the Status widows had a Cancel button in the lower left. Other Status windows had a Close button in the lower right.

If you would like to try and repeat this issue, start several VNC sessions using a batch file something like this:

Code: Select all

Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
Start C:\Users\username\Desktop\VO.VNC
The VNC file used an IP address and a saved password:

Code: Select all

[Connection]
Host=10.0.2.9
password=xxxxxxxxxxxx
port=5900
proxyhost=
proxyport=5900
[options]
disableclipboard=0
viewonly=1
showtoolbar=1
Scaling=1
scale_num=25
scale_den=100
The Status window can appear even if you manually create each VNC session with 2 or 3 seconds between each session start. When I manually started the VNC sessions, I got a Status window (that did not close itself) on the 3rd session. You are more likely to see these Status windows if you rush things via the batch file above.

I have seen these Status windows even before changing the server version. So it is not directly related to the recent changes to the server binary.

For what it is worth, VNC survived 18 rapidly created view only sessions and 18 rapidly created full control sessions between two VirtualBox VMs (each VM running W7 pro 64bit). No grey screens among the 36 simultaneous VNC sessions.



2) Refresh needed:
Sometimes the VNC widow is totally black or mostly black. A refresh will usually solve the issue. Again, during my testing of the grey screen issue, I opened many "full control" VNC sessions to the same remote computer. If I opened a dozen such sessions, only one of two would be black screens (in need of a refresh). The black screen can also happen with only one session to one remote computer too. These black screen windows do not correct themselves on their own. If windows change on the remote computer, then those areas (and only those areas) will update. The rest of the VNC window remains black. The server and viewer settings are default - except what you see in the VNC file above (e.g. Scaling).



3) Lock up:
The work around for the grey screen issue was to keep opening VNC sessions until one of them worked. Sadly, one day I restarted a remote computer using the one VNC session that worked. That left me with about 30 VNC sessions that were in the grey screen mode - but that grey screen mode did not prevent those 30 VNC sessions from attempting to automatically reconnect to a remote computer that was rebooting. That many VNC reconnect attempts locked up my W7 pro 64bit (i5-3470 CPU with 16GB RAM) computer. Even after the remote computer had rebooted (and was available for reconnection), the multiple VNC sessions on my computer where maxing out the CPU and making the computer useless. Even the time/clock stopped updating. Ctrl-Alt-Del did nothing. I let the computer sit in that state of over an hour. It never recovered. I was able to repeat this lockup using two W7 pro 64bit VMs and 10 VNC sessions.

Is there a setting in the VNC shortcut files (INI files) that prevents automatic reconnection attempts? I understand that it is not normal to open lots of VNC sessions to the same computer, but I often have VNC sessions going with more than a dozen different computers. If my desktop computer got disconnected from the network, I fear that the same lock up issue could happen.
VncUser2014
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Re: Grey Screen

Post by VncUser2014 »

Yes I can confirm we have seen issue 1 & 2 that you describe too.
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Rudi De Vos
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Re: Grey Screen

Post by Rudi De Vos »

Difference between cancel close button
1) The status screen always open [cancel], before connection.
[Close] is while connected

[cancel]: disconnect the viewer -> This should indicate that a connection fail, you try to connect to a pc that doesn't have
vnc running or can't connect, the network socket is waiting for answer until timeout.

[close]: close the status window, it just close the status window, doesn't disconnect vnc

A running viewer put the close button active and desactiavte the cancel.
UsernameIssues
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Re: Grey Screen

Post by UsernameIssues »

I did see one permanent* grey screen today. Refresh did not help. I confirmed that the new server version was in use.

*sometimes (if VNC sessions already exists) subsequent VNC sessions will be all grey for a second or two. This is not a problem.

For what it is worth: the permanent grey screen today was between two W7 pro 64bit computers. The remote computer most likely did not have any other VNC sessions at the time. In other words, the permanent grey screen happened on the first VNC session.

Also, the "Refresh needed" windows can be mostly grey too. If left alone, everything remains grey unless a window changes on the remote computer.
Last edited by UsernameIssues on 2016-09-20 19:30, edited 1 time in total.
UsernameIssues
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Re: Grey Screen

Post by UsernameIssues »

Rudi De Vos wrote:Difference between cancel close button
1) The status screen always open [cancel], before connection.
[Close] is while connected

[cancel]: disconnect the viewer -> This should indicate that a connection fail, you try to connect to a pc that doesn't have
vnc running or can't connect, the network socket is waiting for answer until timeout.

[close]: close the status window, it just close the status window, doesn't disconnect vnc

A running viewer put the close button active and desactiavte the cancel.
I should have mentioned that these unrequested/undesired Status windows have no impact on the VNC sessions. I tested just now using the batch file (that I posted earlier) to rapidly create 18 view only sessions. I got two "Cancel" Status windows and two "Close" Status windows. I closed all four Status windows using either the "Cancel" or "Close" button. I still had 18 good (none grey) VNC sessions.

I think that these Status windows are always created. Sometimes they are not visible if the VNC session is created quickly. The Status windows that I'm talking about seem to be orphans that have lost their connection (handle?) to any particular VNC session (parent process?).
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Rudi De Vos
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Re: Grey Screen

Post by Rudi De Vos »

Normal, i just start 2x vncviewers and kill them after 10 seconds.
This script then run for a few hours to test the server.

Using 20+ viewer i can crash the server... nice test but no real life situation.
The changes look stable even when you can force a script crash.

Code: Select all

:loop
start vncviewer -connect localhost -password mypass
timeout /t 2
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
start vncviewer -connect localhost -password mypass
timeout /t 10

taskkill /f /im vncviewer.exe


goto loop
UsernameIssues
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Re: Grey Screen

Post by UsernameIssues »

Did you see orphaned Status windows when you ran your script?

If not, then maybe something is different when starting VNC by rapidly running several VNC [INI] shortcut files like the one that I posted.

You are correct, there is probably no real life use for a batch file that connects one VNC client to the same VNC server like my batch file did. It was meant to let you easily reproduce the orphaned Status window issue. That same batch file can be used to see one or more VNC windows that must be refreshed before they show the contents of the remote computer.

In real life, I script the starting of more than a dozen VNC sessions - but each session is to different computer - so different VNC servers.

In real life, I have been in classrooms where the instructor asks 30+ students to double click on a VNC shortcut file that connects their computer to the instructor's computer. There is a good chance that the instructor's VNC server got 30+ connection requests within a second or two.
VncUser2014
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Re: Grey Screen

Post by VncUser2014 »

Do you know when a new 'official' release will be available for the fixed vnc server? I can update all our VNC servers with your new winvnc.exe but would prefer to use an official release package if it's only a matter of days / weeks.
chuck
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Re: Grey Screen

Post by chuck »

I have this problem too.

If I select "Hextile", "RRE", "CoRRE", or "Raw", this screen is ok.
Other encodings will give a grey screen, not immediately, after used for a few minutes.
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