terry carmen nhdnrcnysupportcom one 4 incoming mail servers get stuck whatever reason queue mail couple hours noticed verify general server health qshape command however generally speaking postfix thing mail come go undeliverable messages generate delay notices hang around expire point returned sender undeliverable isnt much regular admin work needs done aside configuration choose hold messages based size spamminess content whatever case would need find write maintenance utility however default really doesnt need much terry fri 08 aug 2008 041821 0500 monitoring queue mechanisms