Add/Remove Group Membership - Exchange Distribution Groups

This is a two part question...

1. Is there a way to select a user, and add/remove them to multiple Exchange Dist Groups at the same time? If this is possible, I don't see where to do that...

2. Regardless, if I go to Resources and browse the Exchange groups, when I right click and choose "Add/Remove Group Memberships", I get the error below. I can't seem to figure this out. ("I don't know how to initialize without a proper IHaveEditableMemberships account!)

Thanks in advance, still learning this software package.