I’ve just installed Mail-in-a-Box in a DO droplet.
Everything is “green” on the status page yet I can’t receive emails, just send them.
I’ve checked the reverse DNS on mxtoolbox.com and seems okay.
Edit: have also checked MX record on mxtoolbox and says it’s pointing at the MIB box.
SOLVED: the problem was that I had a runbox account setup for this domain and another one. Forgot to remove the alias for the domain I was testing MIB with.