| Event Id | 1229 |
| Source | MSExchangeMTA |
| Description | An interoperability error occurred with entity <object name>. The wrong functional units have been requested. Unable to accept a downgrade on the session protocol data unit (SPDU). Control block Index: <index name>. Requested functional units: <value>. [< |
| Event Information | The diagnostics logging levels of the message transfer agent (MTA) Interface and Interoperability categories should be increased to create interoperability logs. These logs are text logs that consist of the binary contents of communication among MTAs in different sites and between MTA and client applications within a site. They are stored in the \Exchsrvr\Mtadata directory. The current log is always named Bf0.log. Prior logs are named Bfx.log, where x increases as the age of the log increases. |
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