Hi Brett!
To find out the version of client being used by Backup exec, please follow the following. The client version listed for the account with which you connect to the mailboxes to backup is the required client version.
Extract from the MSKBA given by you:
http://support.microsoft.com/?kbid=288894
Use Exchange System Manager to determine the version of MAPI clients that connect to the mailbox store. In Exchange System Manager, locate the Logons container of the mailbox store. The Client Version column displays the version of the MAPI clients that are connected to the mailbox store.
Important The MAPI client version is listed in Exchange System Manager as X.0.Y.Z. This version must be entered as X.Y.Z in the registry value. For example, if Exchange System Manager lists the MAPI client version as 5.0.2819.0, enter 5.2819.0 in the Disable MAPI Clients registry value.
Important Server-side Exchange components also use MAPI to log on. Some components report their client version as an Exchange build number. Therefore, avoid restricting 6.x.x on Exchange 2000 computers or on Exchange 2003 computers.
Hope it helps.
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Additional Information :
For information on the recent VERITAS Backup Exec security vulnerabilities, including links to the downloads for the necessary hotfixes, please refer to the following document:
Patch summary for Security Advisories VX05-001, VX05-002, VX05-003, VX05-005, VX05-006, VX05-007
http://seer.support.veritas.com/docs/277429.htm
Regards,
Ashutosh
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