| Event Id | 957 |
| Source | MSExchangeTransport |
| Description | Connector restrictions (by the group or by the user) are present in the organization. However, restriction checking is disabled. Set the registry value HKLM\SYSTEM\CurrentControlSet\Services\RESvc\Parameters\CheckConnectorRestrictions to 1 (DWORD) and restart resvc and smtpsvc to enable restriction checking on local machine. |
| Event Information | According to Microsoft: CAUSE: If you need to apply a distribution list-based restriction to a connector, you must manually enable the checking process for these restrictions. Restriction checking is controlled by a registry key that must be set on the Exchange bridgehead that is the source for the connector that is being checked. If you specify a restriction, but do not create the registry key, the restriction is not checked. Connector restriction checking is turned off by default because it can significantly affect performance to expand distribution groups and check the restrictions for each message that passes through the system. If possible, turn on this setting on where it is necessary (for example, on the bridgehead server for the restricted connector). RESOLUTION: To resolve this issue: 1. Start Registry Editor (Regedt32.exe). 2. Locate and click the following registry key: HKEY_LOCAL_MACHINE/System/CurrentControlSet/Services/Resvc/Parameters/ 3. On the Edit menu, click Add Value, and then add the following registry value: Value Name: CheckConnectorRestrictions Data Type: REG_DWORD Radix: Hexadecimal Value: 1 4. Quit Registry Editor. 5. Restart the Microsoft Exchange Routing Engine service and the Simple Mail Transfer Protocol (SMTP) services for this change to take effect. |
| Reference Links | XCON: Connector Delivery Restrictions May Not Work Correctly |
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