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Don't understand [DIS_UAC]

Single Click discussions / bugs
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cgallery
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Don't understand [DIS_UAC]

Post by cgallery »

I guess I don't understand what "[DIS_UAC]" is supposed to do.

I'm using the online creator (UltraVNCSC update 2009).

I've added "[DIS_UAC]" and "[DIRECT]" to my helpdesk.txt file directly after my "[HOST]" entries.

I upload the ZIP file and take the resulting EXE to a Win7 machine for testing.

The Win7 machine has a user logged in as LIMITED (NOT ADMINISTRATOR). I start the SC executable, and it asks for the password of the administrator account on that machine. I enter that, and the SC application comes up and I'm able to start a connection.

Now, from within that connection (on the machine I'm using for remote control) I might do something like a right-click an icon and then "run as administrator" or Control Panel/Programs and Features/Turn Windows features on or off (anything that would require UAC) and my connection halts and the machine running the SC app is at a UAC prompt.

Is this normal? Am I doing something wrong?

Can I only do this if the user running the SC app had administrator privs?
B
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Re: Don't understand [DIS_UAC]

Post by B »

Worse, as far as I understand you can only do it if the VNC server is running as a <b>service</b>. I believe that's part of the reason the SCPrompt and ChunkVNC single-click wrapper projects exist - to easily deploy an SC as a service and work better with Vista/Win7....

... but I don't really know. :(

See also [post=66926][/post]

http://www.uvnc.com/install/cmdline.html

It sounds as if all that DIS_UAC really does is prompt for UAC elevation once rather than several times?
Last edited by B on 2010-07-01 20:44, edited 2 times in total.
YY
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Re: Don't understand [DIS_UAC]

Post by YY »

cgallery wrote:The Win7 machine has a user logged in as LIMITED (NOT ADMINISTRATOR).......

Now, from within that connection (on the machine I'm using for remote control) I might do something like a right-click an icon and then "run as administrator" or Control Panel/Programs and Features/Turn Windows features on or off (anything that would require UAC) and my connection halts and the machine running the SC app is at a UAC prompt.
The UAC is a feature for protecting your system. It achieve this by popping up a confirm window whenever any important change will be apllied to the system, and this confirm window MUST BE RESPONSED BY A REAL HUMAN USING THE REAL KEYBOARD/MOUSE OF THAT PC.

Of course, the user must be having enough user right (like administrator) in order to do so.

When running the SC.exe with the [DIS_UAC], if the logged in user is Admininstrator, the UAC prompt will pop up as well, but just once and ask for a confirm (i.e. to disable UAC), and then no more UAC prompt until the connection ended.


In your case, since the logged in user is a limited type, he/she is not able to change the UAC setting.

For verify, you may try to run your SC.exe with an Admin user to see if it can run as what I supposed to be.
cgallery
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Re: Don't understand [DIS_UAC]

Post by cgallery »

YY wrote:For verify, you may try to run your SC.exe with an Admin user to see if it can run as what I supposed to be.
Yep, that works just as you'd expect it to. Shame I can't figure out a way to make it work as a limited user.

I suppose I could explore ChunkVNC, but kinda like the simplicity of SC.

I tried running SC as a limited user (having to enter login name/password for the admin account on the machine). Then I tried SHIFT-RIGHT-CLICKING a cmd prompt and running that as the admin account. But when I then attempt to launch things like Control Panel from the command line (by typing "control"), I get an error that says "Windows cannot access the specified device, path, or file. You may not have the appropriate permissions to access the item."

Which kinda sucks.
cgallery
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Re: Don't understand [DIS_UAC]

Post by cgallery »

Another option that would work, but doesn't...

"Back in the day" of XP, I'd supply a user with a machine that had a limited user account and also an account with admin privs.

If I had to help them remotely, I'd have them run the SC client and get into their limited account. I could help 'em w/ E-Mail, etc., with no problems. If I needed more advanced stuff, I'd open a CMD prompt with a right-click and RunAs, using the account w/ admin privs.

From that commant prompt I could do things like "nusrmgr.cpl" and I'd be in the user applet of control panel, with admin privs. Very handy.

But I can't find a way to make this work in Win7.

Any ideas?

Obviously, I'd have UAC disabled in this case. I've experimented with this and it seems to work. I just can't get to the point where I can launch control panel applets and get them to run w/ admin privs.

Any and all help appreciated.
YY
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Re: Don't understand [DIS_UAC]

Post by YY »

See if this page: Windows 7 - Elevated Command Prompt can help.
cgallery
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Re: Don't understand [DIS_UAC]

Post by cgallery »

YY wrote:See if this page: Windows 7 - Elevated Command Prompt can help.
Yep, I do that, but...

I am logged in as a limited account, so I have to enter the login name/password for the admin account.

Once I've done that, I can't seem to use that elevated command do get much done. In XP, I could do "explorer /separate" and then "Control" and I'd get a copy of control panel, and everything I'd run would run with admin privs. Not so with Win7.

Or in XP, I could run control panel as a limited user but I could Shift-Right Click on icons and do "Run As." This doesn't work in Win7, either, I don't think.
B
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Re: Don't understand [DIS_UAC]

Post by B »

Good questions I guess, but since the SC session was started in limited user mode, I almost think it's a good thing that you're prevented from doing administrative things outside the scope of that running program's privileges. If you can elevate easily enough (and it sounds like you can) then why not just temporarily install a WinVNC <b>service</b>, disconnect, reconnect to that privileged service, and get done what you need to do?

A hacky workaround, I realize, but you could get your work done...
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