Question : invalid email recipient / LDAP

i keep receiving reports stating that i am allowing emails to be delivered to invalid email address in my system.

"Your mail server is accepting invalid email. To improve the performance and accuracy, please configure your mail server to not accept email to invalid recipients and/or domains. You may also want to verify your LDAP server configuration."

where do i begin?

Answer : invalid email recipient / LDAP

there looks to be something wrong with whatever firewall you are using, and the barracuda device.

Check this link
http://forum.barracudanetworks.com/bb/viewtopic.php?t=4469&highlight=mail+server+accepting+invalid+email+improve+performance+accuracy+configure+mail+server+accept+email+invalid+recipients+domains+may+verify+ldap+server+configuration

also this link
http://forum.barracudanetworks.com/bb/viewtopic.php?t=6087&highlight=mail+server+accepting+invalid+email+improve+performance+accuracy+configure+mail+server+accept+email+invalid+recipients+domains+may+verify+ldap+server+configuration

You might want to check to make sure that you have the lastest updates for that, or open a case with the tech support.