How to gain access to a user’s source mailbox post migration
Post migration the source user’s mailbox is left in a “dormant state” so that if the need arises you can roll back the user. However, you may want to access the source mailboxes data without having to roll the source user back. This article will explain how to access a source mailbox post migration after migration using the Priasoft Migration Suite for Exchange.
Several properties are set on the source object post migration to place it in a “dormant state”. This is done to allow for roll back and to prevent unauthorized access to the source post migration. The main property that will block access to the source mailbox data post migration is the ProtocolSettings attribute on the users source AD object.
The ProtocolSettings attribute on the source user object in the Active Directory stores client access settings. This attribute is a multi-valued string property, where each string applies to a different protocol. MAPI access is restricted by adding the following string to the ProtocolSettings:
MAPI§<Bool1>§<Bool2>§§§§§§
The eight § separators define exactly nine fields. The meanings of the fields are as follows:
| MAPI | Specifies that this string contains settings that apply to the MAPI protocol |
| Bool1 | 0 to block all MAPI access; 1 to determine MAPI access based on Bool2. |
| Bool2 | 0 for “no effect”; 1 to deny access to non-cached mode Outlook clients |
| Remaining 6 fields | Currently not used |
If there is no MAPI string in ProtocolSettings, all MAPI clients are allowed.
In order to gain access to the source mailbox post migration you will need to clear the MAPI§ setting in the ProtocolSettings attribute on the source mailbox.
Please note:
Changes to this setting do not take effect immediately and can up to two hours to take effect. This is because, as with others mailbox properties stored in the DS, ProtocolSettings are cached in the MIBCache (default TTL = 2hrs) and in DSAccess (default TTL = 15 min). These caches may delay the time it takes for a change in the ProtocolSettings to become effective.
In order to read more about the Information Store cache, please see the following article: http://support.microsoft.com/?id=179065
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