Why can't the COM port be opened?

Question

Iron

After installing the drivers for the Epson printer, problems began with the availability of the com port. I removed the firewood, but the port is still not available. An attempt to determine who he is busy with using "process explorer + search for handle \device\serial0" did not give anything. It turns out the port is not occupied by anyone?
Only disabling the port in the device manager with a reboot helps. But you don't have to do it every time, do you?

Answer 1

the rights at the user not administrator's?

Answer 2

Check UAC and local policies in gpedit.msc for more.
You may need to run with admin privileges + UAC with elevated privileges