Exchange Server Cookbook

8.1. Blocking Specific Versions of Outlook from Connecting

Problem

You want to be able to control which versions of Outlook connect to your Exchange servers using MAPI, to prevent users from running older, unpatched versions or from running beta versions. Or you may want to completely disable the use of MAPI.

Solution

Using a graphical user interface

1. Log on to the server where you want to block certain versions of Outlook from connecting. You must perform the following steps individually on each server.

2. Using Registry Editor (regedit.exe), locate the following registry key:

   HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\ParametersSystem

3. Add a REG_SZ value named Disable MAPI Clients. For the value data, enter a string containing a list of the MAPI client versions you wish to prevent connecting in one of the formats listed in Table 8-1. (You can get version data in ESM by checking the Logons node under each mailbox database; the Client Version column will tell you what clients and versions are currently in use.) You can specify multiple versions and ranges by separating them with commas.

Table 8-1. Registry formats for blocking Outlook connections

Format	Effect	Example
Maj.min.rev	Blocks the specified version only	9.0.0 blocks all versions of Outlook 2000
maj.min.rev.build	Blocks everything except the specified one	11.6359.6360 allows Outlook 2003 SP1, but nothing else
oldversion-newversion	Blocks all version in the specified range	8.00.3511-8.5.7806 blocks all Outlook ...