Thank you for that information. My computer is not that slow, both drives C/D are SSD and the PC starts faster than my "modern" office computer, even though the PC is already 10 years old. I have tried VarahfLaunchDelaySeconds 10, 12, 16, 20. Neither work better. The effect is always the same. Let's assume 20. Then VARA HF starts, then exactly waits exactly the given delay of 20 seconds, then it (VARA HF) terminates/closes. That repeats two times (always, using any value 5 to 20) then finally VARA HF stays open and VarAC starts. Therefore I assume that this delay value is not the cause of the problem.
[VARAHF_CONFIG]
VaraModemType=VaraHF
VarahfLaunchDelaySeconds=20
VarahfMainPath=D:\Programs\VARA\VARA.exe