Hi Daniele/John
Are you receiving new QSO and the issue is only on receiving callsign from JT, or you cannot receive anything from JT?
If I type (or double click) a callsign into the WSJT-X DX Call field it does not transfer to the Log4OM v2 window.

WSJT-X works fine just doesn't transfer to Log4OM. Fwiw, if I click on log qso in WSJT-X, it does log it (into both v2 and v1)
Thanks John but I tried deleting them and starting fresh, reboot machine after deleting them, cut and paste from the pdf file, considerable amounts of swearing and cursing, several cups of coffee and walking away, none of them made the slightest difference unfortunately. I'll pull out some more hair and have another go at it this morning - right after another coffee
Cheers
David
VK7YUM