up2date – unknown GPG signature

I had previously installed lftp – can’t remember from where but it was now stopping up2date due to a missing key.

The package lftp-3.7.3-1.el4.rf is signed, but with an unknown GPG key. Aborting…
Package lftp-3.7.3-1.el4.rf has a unknown GPG signature.
Aborting…

I need to sort out the key but temporarily sorted with:

up2date –nox –configure

and set

useGPG to No

then

up2date –update

then set the GPG key back to Yes.