Failed to stop postfix.service: Unit postfix.service not loaded

Question

When I try to remove postfix I get this error:

Removing postfix (3.1.0-3) ...
Failed to stop postfix.service: Unit postfix.service not loaded.
invoke-rc.d: initscript postfix, action "stop" failed.
dpkg: error processing package postfix (--remove):
 subprocess installed pre-removal script returned error exit status 5
Processing triggers for libc-bin (2.23-0ubuntu3) ...
Errors were encountered while processing:
 postfix
E: Sub-process /usr/bin/dpkg returned an error code (1)

Answer 1

The reason was because /etc/init.d/postfix did not exist.

I created a blank /etc/init.d/postfix file and made it executable using sudo chmod +x /etc/init.d/postfix, then problem solved.