The following events should be logged by all Microsoft Exchange Server gateways. An individual gateway may log additional events.
| Category | ID | Type | Event | Description |
|---|---|---|---|---|
| 1 | 1100 | Informational | Gateway starting. | Gateway starting. |
| 1 | 1101 | Informational | Gateway started. | Gateway started. |
| 1 | 1102 | Informational | Gateway stopping. | Gateway stopping. |
| 1 | 1103 | Informational | Gateway stopped. | Gateway stopped. |
| 2 | 1200 | Error | MAPI logon failed. | MAPI logon failed: Error (%1). |
| 2 | 1201 | Error | Unexpected error from MAPI. | MAPI Error (%1). |
| 4 | 1400 | Error | Unable to access registry. | Error accessing registry: Error (%1). |
| 4 | 1401 | Error | Unable to access configuration information. | Error accessing configuration information: Error (%1). |
| 4 | 1402 | Error | Unable to open audit log. | Unable to open audit log: Error (%1). |
| 4 | 1403 | Error | Unable to write audit log. | Unable to write audit log: Error (%1). |
| 4 | 1404 | Error | Unable to initialize gateway. | Unable to initialize gateway. |
| 5 | 1500 | Error | Memory allocation error. | Thread (%1): Memory allocation error. |
| 5 | 1501 | Error | Unable to create thread. | Thread create failed. |
| 5 | 1502 | Error | Unknown system error. | Unknown system error (%1). |
| 6 | 1600 | Warning | Address mapping failed. | Address mapping failed. Message (%1) may be non-delivered for recipient (%2). |
| 6 | 1601 | Warning | Message translation failed. | Message translation failed. Message (%1) may be non-delivered. |
| 6 | 1602 | Warning | Unexpected message class received. | Unexpected message class received: Class (%1), ID (%2). |
| 6 | 1602 | Warning | Message nondelivered. | Message (%1) nondelivered for recipient (%2). |
| 7 | 1700 | Warning | Failed connection attempt to foreign system. | Failed connection attempt to foreign system (%1). |
| 7 | 1701 | Error | Communications error. | Communications error (%1). |
| 7 | 1702 | Warning | Connection attempt from unknown foreign system. | Connection attempt from unknown foreign system. |