How do I deal with Google Group spam pretending to be from Google group?

Question

I have a closed google group that I administrate as the only owner. Only members are allowed to send email to this group. For purposes of this example, let's say it's called "my-group". Normal users receive mail that says it is from [email protected] when a group member sends mail to the group address.

Recently the group spam filter has filtered many messages purporting to be from [email protected]. This is the spam filter for the google group, not the spam filter for my email account. This address is not a member of the group; it is the group address. Can this address be safely blocking without breaking normal group usage? Or is there another way to prevent messages that are not from the group from getting to the group spam filter?

Answer 1

There is a suggestion to change the settings below... taken from another site.

Right, this is a new spam technique - At least a dozen of my google groups have been spammed this way already. If you reject the spam messages, it sends an annoying rejection message to all the members of the group! To prevent it go to Manage > Settings > Moderation and set Spam Messages to "Immediately reject them". Leave the spam you've already got unmoderated and it will go away after 7 days (I think).