Authenticate in Dovecot with plus "+" sign in address

Question

We have dovecot 1.0.15, and when I try to authenticate with email "a+b", I fail to do it. But with email "a_b" it's OK. We didn't configure any "plus addressing" in dovecot. Could anyone please give me advice how to fix this problem with authentication in dovecot with emails that have "+" in address? Thanks in advance!

Answer 1

Just add + to auth_username_chars in your dovecot.conf

auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@+

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