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viewer crash on UAC prompt even if server is "as a service"

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ienaxxx
Posts: 1
Joined: 2015-03-17 14:39

viewer crash on UAC prompt even if server is "as a service"

Post by ienaxxx »

Hi all, have a strange behavior using UVNC 1.2.0.1 on both client and server.

Client is Win7 or Win8
Servers on which there is the problem: Win8 (and 8.1)

When i enable the "display query window" (with a timeout of 60 seconds and a default action of "refuse", to be precise) on the win 8(.1) server, each time there is a UAC request for username and password the viewer closes itself unexpectedly and i need to reconnect (asking the person again to accept the request).

I think there's a little bug with this. I searched the forums for "UAC crash" and "query window crash" but i was unable to find a case that is related to mine...

thank you in advance for any help... :-)
gorgo
Posts: 3
Joined: 2015-06-16 12:13

Re: viewer crash on UAC prompt even if server is "as a servi

Post by gorgo »

I have a very similar problem.

UltraVNC Server is running as sevice on Win8.1, query window is enabled, default action is refuse.
When UAC kicks in the connection is lost. The viewer doesn't crash in my case.

When I try to reestablish the connection I get a "authentication rejected". As soon as the UAC prompt on the server is gone i can reconnect.

I have tried with versions 1.1.9.6 and 1.2.0.6. Same behaviour in both versions.

Any ideas?
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Rudi De Vos
Admin & Developer
Admin & Developer
Posts: 6863
Joined: 2004-04-23 10:21
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Re: viewer crash on UAC prompt even if server is "as a servi

Post by Rudi De Vos »

UAC disconnect is normal, not a crash.
Historical vnc was made for single sessions, in the latest OS's MS use multiple sessiosn ( logon/UAC/default...) WIthout drastical changing the
software, the service just restart winvnc in the active session and we added a viewer auto reconnect.


UAC opens a temp new secure desktop (session), winvnc need to switch the desktop and restart in the secure UAC desktop.
If the viewer does not have autoreconnect enabled you need to manual reconnect else the reconnect happen in background.

Because the server is restarted and you have the option query +refuse -> the conection is refused if the remote user does not accept again.

Perhaps thoose options make a difference ( see http://www.uvnc.com/docs/uvnc-server/69 ... ncini.html)

Try
QueryIfNoLogon=0
or
QueryAccept=2 and QueryIfNoLogon=0
gorgo
Posts: 3
Joined: 2015-06-16 12:13

Re: viewer crash on UAC prompt even if server is "as a servi

Post by gorgo »

Hello Rudi,

thanks for clarification how UAC is works in UltraVNC.

We have the following settings in ultravnc.ini

QuerySetting=4
QueryTimeout=30
QueryAccept=0
QueryIfNoLogon=0

Setting QueryAccept=2 seems to solve my problem, the viewer automatically reconnects after a few seconds.
What is the difference between QueryAccept=0 and QueryAccept=2, both is described as "refuse" in help.
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Rudi De Vos
Admin & Developer
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Posts: 6863
Joined: 2004-04-23 10:21
Contact:

Re: viewer crash on UAC prompt even if server is "as a servi

Post by Rudi De Vos »

http://www.uvnc.com/docs/uvnc-server/69 ... ncini.html

QueryAccept=0 ( 0=refuse 1=accept 2=refuse)
This popup a timed messagebox to allow the user (server site) to allow/reject an incoming connect.

QueryIfNoLogon=0
Disable/enable query settings when no user is logged.

If the user is logged on, but has his screensaver on you normal can't get access as "QueryIfNoLogon" find a logged user.
to overwrite this set QueryAccept=2 and QueryIfNoLogon=0 -> no messagebox when screen is locked.
gorgo
Posts: 3
Joined: 2015-06-16 12:13

Re: viewer crash on UAC prompt even if server is "as a servi

Post by gorgo »

Oh, I see...
I totally overlooked that part. :oops:

Thanks again!
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