Chunk problems in Windows 7

[KevCar]

I am using Chunk with a repeater for some of my clients and I am running into an issue. I am unable to access tcpip properties. When I go into the properties of my lan adapter I am unable to click on the ip4 settings to make changes. The mouse moves around but it will not allow me to go into it. This only happens on windows 7.

[Rat]

I'm pretty sure that this is because you don't have administrative permissions... AFAIK the only ways around this is to ask the remote operator to do it for you or to install Chunk as a service.

[B]

You might (?) be able to have the user open an administrative command window and then reconfigure the settings that way.

http://www.howtogeek.com/howto/windows- ... a-run-box/

http://www.petri.co.il/configure_tcp_ip_from_cmd.htm

[KevCar]

I believe it has to do with the viewer itself. With the Chunkvnc viewer I am unable to select some things, like the ip4 settings ( infact it drops connection), but if I issue a command using another viewer and attach to it I am able to do everything. I downloaded a single file, vncviewer.exe, and from a commandline typed in vncviewer -dsmplugin *** -proxy x.x.x.x::5901 ID:chunk ID and it connected and had no problems. I only have issues with the chunkvnc viewer. Using the latest Chunk VN. PC's having issues are Win7 only. XP works fine.

[B]

Well, keep in mind that the ChunkVNC server and viewer are really just UltraVNC after all. My best guess is simply that your problems were fixed in newer versions of UltraVNC. I think Chunk is a few versions behind at this point.

You should be able to drop the latest UltraVNC counterparts into your ChunkVNC setup. I've done that in the past.

[Rat]

Well I believe that I've noticed that when a Window is open that requires administrative access such as the network adaptor settings, that Chunk won't allow any user interaction, although it will with other windows in the same session. I use my ChunkVNC "Fork" which is based on UltraVNC 1.0.9.6.

[B]

So why do you think a standalone version of the same vncviewer.exe would behave differently/better?

[KevCar]

Thanks for the link. I will try it out. I do believe it has to do with the version of the viewer. When I get more time I will try and post back.

[KevCar]

Now I am confused. Now both versions are working fine. Not sure what is causing it. I did get a notice from windows asking if it wanted to allow vnc to make changes. I have seen that before but this time chose no to see what that would do. I guess more testing is in order.

[Rat]

I was able to reliably reproduce this behaviour by opening the Task Scheduler and attempting to create/modify a task.

Firstly a UAC warning appeared. Once the remote user had OK'd the UAC, I was unable to interact with the session until the remote user had closed the Task Scheduler window for me.

My interpretation for this behaviour was that after acknowledging the UAC warning, the Task Scheduler was running under a different user account or permissions set from the ChunkVNC service which was therefore blocked.

What do you think?

[supercoe]

Rat,

Correct, when a program has elevated itself to administrator privileges via UAC you will not be able to control it because the UltraVNC Server executable is running in with the privileges of the user account. Installing as a service allows the UltraVNC Server to run at the highest privilege level all the time.

I've noticed that if I'm running InstantSupport normally and have the customer run a program that prompts UAC (such as a printer installer) if I happen to click anywhere inside the programs window I will loose all control unless the customer finishes the installer or brings up a non admin program into focus.

Interesting results that KevCar has had, the Viewer version should have no effect on what the Server is allowed to control.

For testing purposes any UltraVNC viewer supporting the current command line set can just be dropped into the \Viewer\Bin folder.

[Rat]

Hmmm... So the basic issue becomes:
"How can I prompt the user to run ChunkVNC as an administrator in the first place?"

The AutoIt RunAs function allows users to enter a new username and password to run an executable. I'm thinking of adding an optional dialog to ChunkVNC which prompts the user to enter an administrative login before running ChunkVNC.
What do you think of this approach?

[supercoe]

I don't like always running as admin simply because I support a lot of people that are on domain managed networks, some of which I do not always have the administrator password for.

This is why the ReRun as Admin tray option exists, for those that just want to elevate but still run out of the temp directory.

[Rat]

Sounds as if you've already fixed this the way I was proposing... time to look at your code and copy it

[supercoe]

I'm sure you could improve it substantially, ReRun as admin was a feature request quite some time ago, I don't use it personally.

[Rat]

Added the "Re-run as Administrator" option to my new ChunkVNC Fork release, version 3.1m.

[B]

I hope you peeked at and stole his other changes; having forks is a mixed blessing!