RDCMan used to work normally on this Windows 11 Pro 25H2 computer, but it recently started opening briefly, showing no saved servers, and then crashing to the desktop. Event Viewer reports Application Error 1000 with RDCMan.exe faulting in KERNELBASE.dll, along with .NET Runtime Error 1026 showing an unhandled System.DllNotFoundException. Reinstalling RDCMan, trying the standalone version, running the .NET repair tool, rolling back updates, and even completely reinstalling Windows did not help. The crash returns as soon as RDCMan is installed and launched. Has anyone found a fix, or is the newest RDCMan release incompatible with this Windows build?
3 Answers
I’m seeing the same behavior on the same Windows 11 build. Downgrading to version 3.1.0.0 stopped the crashes, so this looks more like a compatibility issue in the current release than a damaged .NET installation.
The latest version has caused several odd issues for me, so I would avoid it for now and stick with an older 3.1.x release. Another option is 1Remote, which supports managing remote connections and may be a better replacement if the older RDCMan version is not suitable.
The newest release may be the problem. Try using an older RDCMan build, such as version 3.1.2. Several people are still running that version without the launch crash.

That seems worth trying, especially since the issue came back even after a completely fresh Windows installation.