What to do if UUCP works, but uux does not

System Administration Guide
Chapter 7, Connecting to other computers with UUCP

If you can use uucp to transfer files between two systems, but you cannot use uux, there is a problem with the /usr/lib/uucp/Permissions file. When you use the uucp utility, the remote system requires only the LOGNAME entry in Permissions; uux also requires the MACHINE entry.

To fix this problem, add the MACHINE entry with the name of the remote system, to Permissions. For example, if your local machine, goanna is set up to call obie, the entry for goanna in the Permissions file on obie should look like this:

   LOGNAME=uugoanna MACHINE=goanna \
           COMMANDS=ALL \
           READ=/ \
           WRITE=/ \
           SENDFILES=yes REQUEST=yes

NOTE: The permissions granted in the example above are very liberal and should only be used in closely coupled systems where there is no security risk.