Does editing the email address policy in Exchange 2010 remove addresses

Being able to reply from one of your aliases in Exchange is a question that gets asked a lot, and unfortunately there is no easy solution, despite people asking for it since Exchange 2000. As far as MS is concerned email addresses you have setup as aliases are just a way to route email to you, and that's it. Take a look at this question that talks about being able to send from alternative addresses.

In your situation, what I would suggest is to set up separate mail accounts for these addresses you want to send and receive from, and give the user who needs to access them full permissions, including send as rights. They can then add these mailboxes as additional mailboxes in Outlook, so they can operate them through a single Outlook instance, but they remain as separate entity's.

You can exclude a specific user from a DD group with the Set-DynamicDistributionGroup commandlet. Specifically with the -RecipientFilter option.

Example: Set-DynamicDistributionGroup -Identity MadeUpName -RecipientFilter {((RecipientType -eq 'UserMailbox') -and -not(Name -like 'Journal User'))}

Note that this example is just with recipient type = userMailbox. You can get the current recipientFilter of your DD group and modify it however from powershell.

(get-DynamicDistributionGroup -Identity MadeUpName).RecipientFilter