If you find the below given error in the logs :

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2005-07-23 12:47:44 1DvVMF-0007Wn-Ad == nobody@server.servername R=localuser T=local_delivery defer (13): Permission denied: failed to create directories for //mail: Permission denied
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The solution is :

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cd /

mkdir mail

chown nobody.mail mail

cd mail

touch inbox

chown nobody.mail inbox

chmod 660 inbox
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