VNC, Windows and UAC prompts
Posted by jpluimers on 2019/02/15
Since I needed to maintain a Windows PC behind a VPN connection via the console (so not via RDP sessions) including installation of software, I needed a (preferably free or open source) solution supporting elevation through UAC (User Account Control).
For a good description of differences between RDP and VNC, see [WayBack] remote desktop – TightVNC while an RDP session is running – Super User by [WayBack] User Canadian Luke.
Of the many non functional search results, the one suggesting running UltraVNC as a service is the one that really worked: [WayBack] If you install UltraVNC as a service, you can see the UAC notifications and press the buttons… VNC on windows 7 with administrator rights – Super User.
- I only needed the “Ultra VNC Server Silent” installation (see screenshot below).
- Run the UltraVNC settings (default location for the settings application is
C:\Program Files\uvnc bvba\UltraVNC\uvnc_settings.exe)- In the
Securitytab, be sure to set good passwords for read/write access (VNC Password) and read-settings (View-Only password) - In the
Servicetab, ensure the service is installed and if it is stop+start the service
- In the
- Optionally ensure a TLS or SSH tunnel (as by default ports 5900 and 5800 are unencrypted)
- I need to research this further, as there seems to be a plugin possibility.
Now I can use Screen Sharing on my Mac to access the machine via a VPN over the VNC protocol. Combined with a Wake On LAN feature in the remote network, this works splendid.
Notes
- If you are OK with a full installation of UltraVNC, then
choco install --yes ultravncwill do fine - Alternatively, you can do an install through PowerShell with your own .inf parameters:
- [WayBack] Random-PowerShell-Work/Deploy-VNC.ps1 at master · adbertram/Random-PowerShell-Work · GitHub
- [WayBack] Webinar-Altaro-4-Ways-to-Improve-your-MSP-by-Embracing-Automation-and-DevOps/SilentInstall.inf at master · adbertram/Webinar-Altaro-4-Ways-to-Improve-your-MSP-by-Embracing-Automation-and-DevOps · GitHub (example .inf file)
- [WayBack] Remotely install UltraVNC server to Windows machines in a cinche
- There was no need to open up the firewall ports 5800 or 5900
- One thing I’ve to figured out has to do with keyboard mappings: the Mac local Command key maps to the remote Alt key (using Microsoft Remote Desktop it would map to the remote Windows key), but I’ve not figure out what maps to the remote Windows key yet.
- Note this fails for [WayBack] UltraVNC • View topic – UltraVNC SC – UAC Window Doesnt shown. The reason is that the Single Click version runs as an unelevated user process. So off the list [WayBack] Single Click – UltraVNC VNC OFFICIAL SITE, Remote Access, Support Software, Remote Desktop Control Free Opensource
–jeroen
PS: [WayBack] macos – Wake Other Computers from Mac OSX – Ask Different
PS2: I’m not sure about the difference between “Silent” and regular – see [WayBack] UltraVNC • View topic – UltraVNC Server “Silent” – Install option
The Wiert Corner - irregular stream of stuff 
Leave a Reply