doveadm sending invalid AUTHENTICATE to uw-imap

Chris Candreva chris at
Wed Feb 8 04:24:14 UTC 2023

I'm migrating a legacy uw-imap system to Dovecot, on a Rocky (RHEL) 8 
server running Dovecot 2.3.16-3 from their repos. I am using a master user 
to import all users for an imaps connection from the old server to the 
new. On a trial run however, it worked for about half the users. Half are 
giving an error of the form:

dsync(user): Error: imapc(host:993): 
Command '1 AUTHENTICATE PLAIN xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' failed with BAD: 
1 Missing or invalid argument to AUTHENTICATE

I can't seem to get the IMAP command for the users that did work. However, 
on the face of it, that is an invalid AUTHENTICATE command. If I take that 
string and brake it up into (what I've googled is) the proper form of 
multi-command form of


then the login succeeds. I have not been able to find anyone else with 
this problem in my search. Is this a known issue, is there a way to force 
the multi-line AUTHENTICATE, something else I'm missing ? Any help is 
appreciate on this!


Chris Candreva  --  chris at  --

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