XI Adapter Engine is stuck

[] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] []

Symptom
Your J2EE Engine is stuck. XI/PI Message flow through the Adapter Framework has stopped. On 6.40 and 7.0 systems logon to the Visual Administrator isn’t possible any longer, in 7.1 systems SAP NetWeaver Administrator hangs. System startup failes, hangs or takes very long.
Other terms
Application Thread Manager, Max Thread Count, Messaging System, [...]

Message Overview shows wrong number of messages

[] [] [] [] [] [] [] [] [] [] [] []

Symptom
Messages are stuck in a wrong status in the Message Overview or the counter shows a number that is different from the actual number of XI Messages on the database. E.g. the page shows some Messages that are in a Scheduled status. But when navigating to the detailed Message list in [...]