UltraVNC Viewer Task is stopped at startup

[fdres0]

Hello to all,

we have a problem with a single client. Until a week ago, everything worked perfectly. now we have the following problem: when starting UltraVNC Viewer, apparently nothing happens. In Task Manager the process appears very briefly and then immediately terminates.

UltraVNC version: 1.3.8.1
Windows: 10 21H2

Does anyone have any idea how to solve the problem? (We have already tried reinstalling, unfortunately without effect).

Thank you and best regards