Hello,
we have a group like all@domain.net
and in "delivery management" it was set to "Only senders inside my organization" to prevent spam and all unwanted messages from other companies.
But now we have friendly foreign domain2.net and i want, that someone like user@domain2.net could send message to all@domain.net.
Second domain uses Google Mail and it can't be migrated to MS Exchange and MS AD :(