Where can I change the sender information for e-mail?

[keylevel]

Emails to some recipients are failing as their mail system is checking to
see if it can send a reply to bugzilla.

This is failing and the server log is showing that the mail was sent by
apa...@localhost.localdomain.

Where do I need to go to change these settings to the correct values?

Thanks

[Denis Roy]

Look in the Bugzilla parameters:

mailfrom
The email address of the Bugzilla mail daemon. Some email systems
require this to be a valid email address.

The domain portion of the sender's email address may require you to
configure your mail server - if you use postfix, look at
masquerade_domains, mydomain and myhostname in /etc/postfix/main.cf