Error in Application Log: "No LegacyDN found. Account Disabled" (4348530)

If you delete the account and its mailbox the following event ID will logged in application log:

Getting Exchange properties for Account name caused following error(s)
1: Request to GC://DC=Test,DC=LOCAL failed. No LegacyDN found. Account
Disabled: N/A. Exchange Account Disabled: False ADCDisabledMail: False
ADCMailDisabledbyADC: False 2: Request to LDAP://DC= Test,DC=LOCAL
failed. No LegacyDN found. Account Disabled: N/A. Exchange Account
Disabled: False ADCDisabledMail: False ADCMailDisabledbyADC: False 3:
Specified cast is not valid.

The mailboxes corresponding to deleted Active Directory accounts still exist in the Archive Manager database and must be manually deleted.

You need to locate all mailboxes in question and delete them.

You can locate the Mailbox in the list of Mailboxes displayed in the MailBox Administration form by either:

* scrolling though the list of MailBoxes;
* entering a value in the Name or Display Owner field;
* Choosing a Server from the drop-down list;
* Choosing a MailBox Type from the drop-down list
* Choosing whether the MailBox has been deleted

* Then clicking the Search button once.

Click the Delete button to the left of the MailBox name. The Delete MailBox confirmation message is displayed.
Click the OK button to confirm the deletion. The selected MailBox is deleted, and the MailBox Administration form is displayed.

Alternatively, you can delete a MailBox by opening the Edit MailBox form, selecting Edit an Existing MailBox, clicking the Delete button, and confirming the deletion.

If need to keep mailboxes from deleted accounts then use another way. You need to locate all mailboxes in question and disable them from archiving. After you locate the mailbox, click on edit button. Unselect "Enable Store Management" checkbox. As a result, Exchange System Manager will not process the mailbox and log the above mentioned event ID.