Intermittent IMAP Login failures - about 25% fail

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Fri Apr 8 12:04:38 UTC 2016

I'm not getting a hit on "Dovecot pwck". Can you elaborate.

  Original Message  
From: Mobile Phone
Sent: Friday, April 8, 2016 3:20 AM
To: Dovecot Mailing List
Reply To: support at
Subject: Re: Intermittent IMAP Login failures - about 25% fail

SOLVED: Should anyone else run into this and debugging shows no issues,
just random dovecot logins fails - there was a bad username stored.
"pwck" showed it up.
Only cost me 3 days

On 7 April 2016 at 17:24, Timo Sirainen <tss at> wrote:

> On 07 Apr 2016, at 19:02, Mobile Phone <cell at> wrote:
> >
> > pam(prtg.08dir, pam_authenticate() failed: Authentication
> > failure (password mismatch?) (given password:
> YesThisWasTheCorrectPassword)
> ..
> > Why it this bouncing 25% + of IMAP AUTH LOGINs?
> PAM said that login wasn't allowed. PAM can have all kinds of plugins that
> can do all kinds of things. Maybe you have enabled some PAM plugin that
> denies the user's access even if the password is correct. Unfortunately
> there's no way to enable debugging for PAM. Try simplifying your PAM setup,
> or if you can't figure out anything else switch to passdb shadow.

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