reinstalling the 3030 - how to activate touchscreen?

Recently I had to reinstall an Optiplex 3030. It went very well, except that I couldn't get the touchscreen to work.

There were drivers missing (in the Device Manager) but even after I added and upgraded all I could think of, there was no touchscreen.

Initially I had W7 but I also tried W10. No luck. What am I missing here?

I think I already tried "TOUCHFW_Dell_WIN_A00_Setup-1R8W1_ZPE" but I could always try yet again.

I suppose the functionality could be broken. Advice on how to install or test it is more than welcome.