Article - CS318801
Error "Unable to connect to MQTT in [<Thing Name>] : Timed out waiting for a response from the server" affecting MQTT/MQTTConnection Things showing disconnected in ThingWorx Platform
Modified: 15-May-2026
Applies To
- ThingWorx Platform 8.5 to 9.6
Description
- MQTT / MQTTConnection Templates applied to Things does not appear connected
- MQTT Extension v2.1.0 is not working with ThingWorx 9.x
- Issue not reproducible on ThingWorx 8.4.x
- Properties isConnected, lastConnection of MQTT or MQTTConnection Template never get updated
- Errors in <ThingworxStorage>\logs\ApplicationLog.log:
- With MQTT Template thing(xxx is the name of MQTT Template thing
-
[L: WARN] [O: c.t.t.m.MQTTThing] [I: ] [U: ] [S: ] [P: ] [T: MQTT Rec: /Thingworx//xxx] Lost MQTT Connection For [<Thing Name>] : Exception Was Connection lost [L: WARN] [O: c.t.t.m.MQTTThing] [I: ] [U: ] [S: ] [P: ] [T: MQTT Rec: /Thingworx//xxx] Lost MQTT Connection For [<Thing Name>] : Cause Was null [L: ERROR] [O: c.t.t.m.MQTTThing] [I: ] [U: ] [S: ] [P: ] [T: Thread-53] Unable to connect to MQTT in [<Thing Name>] : Timed out waiting for a response from the server [L: ERROR] [O: c.t.t.m.MQTTThing] [I: ] [U: ] [S: ] [P: ] [T: Thread-53] Unable to close client in MQTT Thing <Thing Name> : Connect already in progress
- With MQTTConnection Template thing(xxx is the name of MQTTConnection Template thing
-
[L: WARN] [O: c.t.t.m.MQTTConnectionThing] [I: ] [U: ] [S: ] [P: ] [T: MQTT Rec: /Thingworx//<Thing Name> Lost MQTT Connection For [<Thing Name>] : Cause Was Connection lost
- MQTT Server keeps getting connected and disconnected continuously
- MQTT connection fails to send data
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