Monday, February 2, 2009

Reverse VNC Helpdesk

Need to support remote users behind firewalls with no way for you to remotely access their machines? Reverse VNC to the rescue!

UltraVNC SC is a single click VNC server that you would create and send to your end users. All they have to do is run the executable and it will connect their machine to your VNC viewer in listen mode.

However, VNC performs very poorly on remote Vista machines with Aero enabled. Also, on Vista if you do something that causes the UAC prompt to come up you get disconnected.

I have come across this modified version of UltraVNC SC that includes some programs to disable Aero and UAC when it is run. When the connection is closed Aero and UAC are then turned back on. This version of UltraVNC SC also works just fine on other versions of Windows. It checks to see if the machine is running Vista before it trys to disable anything.

You can find modified version of UltraVNC SC here: UltraVNC Forums

Modify helpdesk.txt in the SC_VNC_Files folder. The only thing you have to change is [HOST] section, enter your IP/Hostname information here. For more information on the helpdesk.txt file, see

Once you've modified helpdesk.txt, run the Compile.cmd file and it will create your reverse VNC server executable which you will send to your end user.

You'll need to download the UltraVNC viewer:

You can download the full install and only install the viewer if you like. Once you have the viewer, you need to run it from the command line with the listen switch.

vncviewer /listen


vncviewer /listen portnumber

When your end user connects you will get a pop up on your screen confirming the connection. Once you hit ok you will then be connected to their machine.


Tropmonky said...

Any info for getting it working with Windows 7? This custom version doesn't turn off the aero and UAC within Windows 7.

Steve said...

manually disable the display effects, and turn colors to 16 bit, this works for us, as soon as colors drop, its right back to XP sytle speedy support :)

Chris Voce said...


A couple of minor tweaks make it work just as well in Windows 7 (I am so impressed with this new version of the app... we were looking at moving away from VNC until I found this webpage!!).

In the downloaded files, in the root, there is a file called SC_VNC.au3. Edit it, and near the end you see it check for OSVersion=WIN_VISTA. In Windows7 this will be WIN_7 (or WIN_LONGHORN for the release candidate!).

Simply put a couple more if/else/endifs to handle these cases... the switching off of the Aero etc works just as well in Windows 7.

I actually did it slightly differently and passed the OSVersion through to the winvnc.cmd file then handled it in the batch file...

so in SC_VNC.au3, replace the existing if/else/endifs with:

Run(@ComSpec & ' /c "' & @TempDir & '\SC_VNC_Temp_Files\winvnc.cmd '& @OSversion &'"', @TempDir & "\SC_VNC_Temp_Files\", @SW_HIDE)

... then in the winvnc.cmd file, change the IF at the top to be:

IF "%1"=="WIN_VISTA" goto vistafound
IF "%1"=="WIN_7" goto vistafound
IF "%1"=="WIN_LONGHORN" goto vistafound

Hope this helps people,

Chris Voce

Anonymous said...

the post above = win

Anonymous said...


Thanks you for this wonderful application

But i've still a problem

It doesn't turn off the UAC within Windows 7 for the users who are not "admin"

I have make what Chris Voce tell's and it's works for aero.

Have you a solution?

Thank you for your answers!

Tropmonky said...

Chris Voce, THANKS!!!!!!!!!!

Anonymous said...

Download link is dead @ 7/21/2010 9:33am est... would love to get this and try it.

Mondo said...

You should be able to find newer version here on the UltraVNC forums: