At a command prompt in the VPOP3 directory run
psql
(The password is 'vpop3pass')
Then, type
\copy (select conditions, address, server, username, password, outaddress as rewriteaddress, matchcount as matches from rules.lanforwarding order by ruleorder) to 'c:/temp/x.csv' csv header;
(replace c:/temp/x.csv with the actual file you want to write to - you can use \ instead of / if you wish, but you have to double them up - c:/temp/x.csv would have to be written as c:\\temp\\x.csv)
Then, that file is a CSV file which you can read into Excel or something. There are seven columns:
(Just as on the Settings → LAN Forwarding → Configuration page)
N.B. VPOP3 does not need to be stopped while you do this