Portserver & Win10 connect issue

I migrated a working Portserver TS4 from an XP system to a Win10 system. When
I try to access any Comm port there I get the immediate Win10 message ‘an
unexpected network error occurred’.

I downloaded & installed the Win10 setup from Digi website.
The expected Comm ports show up in Device Manager
I have updated the Portserver software via setup.com
I have disabled the firewall.
The wireless network attached to the Portserver is connected with Win10 using a lynksys wrt54
I can access the Portserver via browser.
Should the older Portserver TS4 be compatible with Win10 ?
I suspect there is some ‘gate’ still disabled in Win10 but after some time
I have not found it. Your suggestions would be appreciated.