Hello Jordi, thanks for your tips/advice. I've run the SFC /SCANNOW and not seen the access violation since. Fingers crossed my guts says this was the solution. (more then over a month now. I now run SFC /SCANNOW on regular basis)
Antivirus is build-in Windows antivirus nothing fancy. My TRX is TS890 via HRD software, in Swisslog HRD is set as transceiver control. Swisslog 5.115 installed in C:\Swisslog folder. Running SDRplay RSP1B via Omnirig with SDRuno software. Omnirig set via HRD's 3th party serial port (com0com serial port emulator pair).
Also run WSJT, JTDX, MSHV without problems and communicating smoothly with Swisslog. HRD DM-780 is running just fine.
I also use FLdigi but gives conflict with HRD software so I only run FLdigi now and then but seperately.
Need to be said that in spite of the (past

) access viloation, Swisslog always worked and works very fine for me. I just was wondering why this violation kept appearing on display.
Thanks again and good luck. If I can provide more info please let me know as far my knowledge reaches.
Kindest regards, Adri 73 de pa1adr