Upgrade Issues with Tibbo Device Monitor on Windows


Running an MSI installer for Tibbo Device Monitor results in errors such as:

Can't start core service 'tdevmonc': The system cannot find the file specified

Then installation rolls back. Repeating the process yields the same results.


There is a fundamental problem with all hooks in general and with so-called legacy filter drivers in Windows in particular – it’s not always possible to safely remove them. The key word here is safely – under certain conditions removing a hook would destabilize the system. In such cases, the only way to deal with the issue is to schedule a reboot and after that start with a clean slate.

Due to a bug in the Tibbo Device Monitor MSI installer (fixed in v3.2.3) the reboot flag was not properly set when the filter driver could not be safely detached (and therefore, prevented from unloading). That resulted in the tdevmonс service being removed and re-created by a new version of the Tibbo Device Monitor installer, but the driver from an old version still being kept in memory. Under such conditions, Windows prevents restarting a service.

Starting with Tibbo Device Monitor v3.2.3, whenever it’s not possible to safely detach the filter driver tdevmonc.sys, the MSI installer doesn’t attempt to restart the service and instead asks for a reboot.


The solution is to uninstall the old (pre-v3.2.3) version of Tibbo Device Monitor, reboot manually, and then install a new version.

Open Windows Control Panel, start the Uninstall a program applet, select Tibbo Device Monitor and click Uninstall. Then reboot manually – even if not asked to.

Now the installer for a new version of Tibbo Device Monitor version should work without a problem.