Ditto Clipboard Send to Friends Not Working
Solution 1:
Just in case you still haven't figured it out or for anyone else who stumbles onto this page with the same question - you need to add the computer to the list on the bottom. Just double click on any empty line. Computers in that list will show up in the Send to list.
Solution 2:
Now in 2021. Disable Receiving Clips comes checked by default. Just uncheck it. Adding the computer names and IPs in the friends' section is optional.
Regards, Carlos