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Special Notes / Troubleshooting
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If you have login failures and you are using pass=yes, try commenting it out.
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Problems have been noticed when using the following combination of passdb's in respective order: Master-Users/LDAP/passwd. The intention in that scenario was to first check logins against master users, followed by LDAP, followed by local /etc/passwd. The passwd lookup was on a system that used also used LDAP nameservices which may or may not have been causing problems for Dovecot. But this was solved by keeping the Dovecot LDAP database, and changing the passwd database to "passdb passwd-file -> /etc/shadow" and "userdb passwd-file -> /etc/passwd".
* If still having problems, turning on full authentication debugging and checking the dovecot logs helps to track down what master user authetication is doing.
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Note that with 1.0.beta4 and beta5 the username order was accidentally reversed (ie. <Master-User><Separator><Username-To-Login-As>).