Vuescan Vuex64-9.7.62.deb does not see driver in 20.04LTS

[mark bower]

Ubuntu 20.04LTS system. I installed the Epson driver iscan-gt-f720-bundle-2.30.4.x64.deb.tar.gz then installed the Vuescan Vuex64-9.7.62.deb. When I open VueScan from the drop down menu (MATE user ), it sees the Epson scanner, but does not see that a driver is installed and presents an error message: "VueScan found an Epson Perfection V500, but no Epson softwdre for this scanner was found . . .

I have used VueScan for about 10 years, going through a number of Ubuntu upgrades, but no problem. Ed Hamrick at VueScan has no solution.

Help please.

[mark bower]

Strangely solved. I launched VueScan from the command line and it responded normally with no error message. I then launched VueScan from the drop down menu (using MATE) and it responded normally. Even turned off the computer, restarted, and booted VueScan from the menu again - no problem.