As of 3 days ago, I am getting the following error in the maillog.
postfix/trivial-rewrite: warning: database /etc/postfix/transport.db is older than source file /etc/postfix/transport
The number in the square brackets  is different each time.
When I Google on the error message I find that the solution is to run:
Execute the command "postmap /etc/postfix/transport" whenever you edit the transport table.
Well I may be hacking around in the IDS/IPS rules, but I haven't touched postfix.
Why would the transport table have been changed?
When looking at the transport file, everything is commented out so I can't understand how anything could have changed??
Is it OK to run this command to fix the problem?