To the best of my knowledge, that registry value only applies to Exchange 2003.
See here for Exchange 2007: http://technet.microsoft.com/en-us/library/bb629517(EXCHG.80).aspx From: Miller Bonnie L. [mailto:mille...@mukilteo.wednet.edu] Sent: Friday, January 29, 2010 1:28 PM To: MS-Exchange Admin Issues Subject: Suppress OOF to Distribution Lists Someone at our helpdesk did not get an OOF from another person today, I'm trying to figure out why. After some testing, I'm finding that an OOF message from Person B does NOT go to person A if person A sends to a DL that contains person B. So, I did a quick search and see there is this ability to suppress OOFs to distribution lists (http://technet.microsoft.com/en-us/library/aa997729(EXCHG.80).aspx), but I do NOT have it configured-this value does not exist in the server's registry. Exchange 2007 Ent SP1 RU9 on WS03 SP2 R2 all roles on one server. Any ideas? Do I just need to add the "SuppressOOFsToDistributionLists" value, set it to 0, and recycle Exchange services to make it start working? Is there a good reason that one would NOT want OOFs to go back to users sending to DLs? Thanks, -Bonnie