The Badmail folder contains messages that cannot be delivered into your organisation, and also cannot be returned back to the sender. Therefore, the folder typically contains spam, and the files within the folder can usually just be deleted.


However, Exchange doesn't provide a setting to periodically empty the contents of the folder. The danger is that this folder will go un-monitored, and will continue to fill up.

Try : http://support.microsoft.com/kb/867642


One more script if you are okay with WSF : AutoBad mail content remove download