[Solved] Postfix: “queue file write error”

If you get an error like:

Apr 15 12:41:03 webb4 postfix/sendmail[11234]: fatal: web1_user(12967): queue file write error

in your mail log, then the value for message_size_limit in postfix main.cf is too low.

Solve Postfix queue file write error

Edit postfix main.cf:

nano /etc/postfix/main.cf

and set the message size limit to a higher value. E.g.

message_size_limit = 900000000

and restart postfix:

service postfix restart

If there is no message_size_limit set in main.cf, just add the line.