Error 6 when trying to run Design Database or Netsys

Hi

My computer has suddenly started throwing up an error message when I attempt to run either Design Database or Netsys. I have been using these regularly for several years including up until last week, but now cannot run the software.

I can log on as far as the main menu "Hevacomp Design Software" screen, I can use Mechanical Design apparently as normal.

But when I select Design Database I get "Error 6 - Overflow". If I select Netsys then click on any of the sizing options (Ductwork, Heating, Gas, etc.) the same error message results.

Hevacomp version V8i SS1 SP10 (V8i SS1 CP3 (06/16)).

Windows 11 Pro, Version 10.0.22621 Build 22621.

Connection Client is updated to latest version.

Any help would be appreciated!