MQTT Error - 'An operation was attempted that is illegal in the current mode -"

[ksasikumar]

I am getting this error message when using MQTT Sub and Pub instructions in my program- 'An operation was attempted that is illegal in the current mode or configuration"
I do not know what is causing this error, both 'On success' and 'on fail' bits for the MQTT instructions are usually off. Sometimes 'On fail' will be ON, and i get the exception error 65563, which corresponds to error code 27. However, there is no error code 27. I have spoken to tech support a few times regarding this, but their solution is to restart the PLC. I would like to know what is causing this error in the first place so that I can rectify the issue. Has anyone seen this error message before? Any feedback is appreciated.

[BobO]

I am getting this error message when using MQTT Sub and Pub instructions in my program- 'An operation was attempted that is illegal in the current mode or configuration"
I do not know what is causing this error, both 'On success' and 'on fail' bits for the MQTT instructions are usually off. Sometimes 'On fail' will be ON, and i get the exception error 65563, which corresponds to error code 27. However, there is no error code 27. I have spoken to tech support a few times regarding this, but their solution is to restart the PLC. I would like to know what is causing this error in the first place so that I can rectify the issue. Has anyone seen this error message before? Any feedback is appreciated.

This is most likely related to a bug in the TCP connection code that will hang indefinitely. The new 2.9 firmware fixes it, which we are in the process of releasing. As luck would have it the machine we use for production builds crashed earlier today preventing us from making a minor last minute change, but it's back up now and the release should be tomorrow.

[ksasikumar]

That's good to know, thank you.