Instable input reading K8000 since VB.NET

Hi,

I have a lot of K8000 in operation, operated by an own-written VB6 program. It works wonderfull for years.
I’ve now rewritten my program in VB.NET and since that time, the reading of the analog inputs (0-5V) are no longer stable. (no change of hard-ware, same K8000, same PC).
When I return to the former program written in VB6, it’s stable again. The VB.NET program is a direct translation of the VB6 program, so no new features.

I noticed the problem only on the PC’s where 2 K8000 are connected. On the PC where only 1 K8000 is connected, the VB.NET program works fine and stable.

Both the VB6 and VB.NET program are compiled on the same XP professionsl machine. Programs are operated on another XP professional machine.

I don’t know what can cause the instable reading of the 0-5V analog input. Can anyone help me please? Do I need new DLL files for VB.NET?

Your help is really appreciated.

Best regards,

Wim013