Event ID - 666

Event Id666
SourceMSExchangeMTA
Description The MTA work queue is backlogged with 600 messages in the queue. [MTA SUBMIT 18 231] (14)
Event InformationThe work queue alarm may log two different events to notify the administrator when the work queue reaches a certain size. One event notifies the administrator that the work queue has reached the "alarm on" threshold. This warning is logged with the event ID 666.
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Reference Links MTA Logs Warning Events When Queues Reach Specified Sizes

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