Unable to Enable MailUser

It's rare, but occasionally I run into a need to edit Exchange attributes on user mailboxes manually. Last week I had a situation where a user account had no Exchange mailbox, but did have some Exchange attributes populated.

This left me in a scenario where running Enable-MailUser failed for the user accounts. For some of the accounts, blanking out the HomeMDB attribute was sufficient. However, for two accounts, even after blanking out HomeMDB it didn't work.

When I ran Get-User (the Exchange cmdlet) it reported back that the account was already a MailUser. However, if I ran Get-MailUser I got an error back indicating that: "The operation couldn't be performed because object 'username' couldn't be found on 'servername'".

The fix for these two user accounts was to blank out the two additional attributes:

• msExchRecipientDisplayType
• msExchRecipientTypeDetails

Once those two attributes were cleared, I was able to use Enable-MailUser as expected.

Additional reading:

• A list of valid values and their meanings for msExchRecipientDisplayType and msExchRecipientTypeDetails