I approved an upgrade to TeamViewer 10 and lost TeamViewer access to a machine from the MAXfocus dashboard. I need to downgrade TeamViewer from 10 to 9 to re-gain compatibility with MAXfocus. I only have command-line access to the machine via the MAXfocus Remote Background prompt.
Posts here and here explain that the /S switch (must be capitalized) can be used for silent uninstall and re-install of TeamViewer using the .exe uninstaller and installer (not .msi).
TeamViewer Version 10 gets installed in the Program Files (x86)\TeamViewer folder, not in a subfolder. Also, the service name is just “TeamViewer” without a version suffix.
Fortunately, I still have the TeamViewer 9 installer in a folder called C:\Install on the remote computer. If I didn’t, I’d have to write a script to download it.
Downgrade Instructions
At the Remote Background command prompt:
net stop TeamViewer
"%programfiles(x86)%\TeamViewer\uninstall.exe" /S
That returns immediately. Give it a minute and make sure the TeamViewer folder is empty. Then install the previous version:
"C:\Install\TeamViewer_Setup.exe" /S
Check the Program Files (x86)\TeamViewer\Version9 folder to confirm that Version 9 is there. On the Remote Service Control tab of Remote Desktop, you should see the TeamViewer 9 service running.
From the MAXfocus dashboard, re-run checks to get to to pick up the TeamViewer integration again. If TeamViewer 10 was installed via Patch Management, change that patch from Approve to Ignore so it doesn’t upgrade again.
Additional Steps
Unfortunately at this point you are left with the following message in the dashboard:
Take Control – Existing Installation – Integration Requires "Start With Windows" Set
Options at this point:
- Find another way to access the computer, or have the user work with you. Complete the steps here to Start TeamViewer with Windows.
- Figure out which registry keys need to be changed and change them via the command prompt.
- Give up on the stand-alone version of TeamViewer, at least temporarily. From the dashboard, edit the device and turn on Take Control. This adds a Replace with Take Control link to the device in the dashboard. Click on that to activate the Take Control integration.