Error: Ubuntu 11.10 + saslauthd: SASL PLAIN authentication failed: no mechanism available

You have installed Postfix with saslauthd on Ubuntu 11.10 and get the following error in /var/log/mail.log when you try to send an email:

server1 postfix/smtpd[7868]: warning: unknown[1.2.3.4]: SASL PLAIN authentication failed: no mechanism available

Solution

saslauthd seems to be buggy in Ubuntu 11.10: https://bugs.launchpad.net/ubuntu/+s...l2/+bug/875440

You can solve the problem by installing the saslauthd packages from Ubuntu 11.04:

apt-get install libsqlite0 db4.8-util libssl0.9.8

cd /tmp
 mkdir sasl
 cd sasl
 wget http://archive.ubuntu.com/ubuntu/pool/main/c/cyrus-sasl2/libsasl2-2_2.1.23.dfsg1-5ubuntu3_amd64.deb http://archive.ubuntu.com/ubuntu/pool/main/c/cyrus-sasl2/libsasl2-modules_2.1.23.dfsg1-5ubuntu3_amd64.deb http://archive.ubuntu.com/ubuntu/pool/main/c/cyrus-sasl2/libsasl2-modules-sql_2.1.23.dfsg1-5ubuntu3_amd64.deb http://archive.ubuntu.com/ubuntu/pool/main/c/cyrus-sasl2/libsasl2-dev_2.1.23.dfsg1-5ubuntu3_amd64.deb http://archive.ubuntu.com/ubuntu/pool/main/c/cyrus-sasl2/sasl2-bin_2.1.23.dfsg1-5ubuntu3_amd64.deb

dpkg -i *.deb

Replace _amd64 with _i386 if you have a 32bit system.