Exchange 2007 or 2010 stopping NDR from postmaster@ filling queues

If you find your queues are getting full of NDRs from the postmaster to spammers you can turn off allow non-deliveyr reports in the Hub transport\remote domains\default\properties

This however will stop NDRs from being generated that are valid. You may therefore want to configure anti spam filtering

If running a single exchange server with hub transport on it (i.e. you do not have an edge server in front of exchange) you can enable spam filtering using the instructions here:

http://technet.microsoft.com/en-us/library/bb201691.aspx

Regards,

Brendan King