Waters GI Pump error - instrument not found

We are glad users of a Waters 2535 pump system (with 2489 UV detector) running MassLynx 4.1

We recently experienced an error, that results in an inlet error. 
Despite everything being nicely connected we get a "Waters GI Pump Error :- Instrument Not Found" communication error.

Despite, it is possible to manually adjust the flow on the machine through the Inlet Method tab, so communication seems to be fine and this seems to be a software issue. However, we are currently not able to use the instrument. We have tried several restarts and other suggestions - but the problem persists.

Is there any suggestions how to fix this issue?

Thanks a lot, 

Postdoc at EPFL


  • Hi Alexander,

    We have had some reports of this error happening when and automate defragmentation is scheduled on the PC.  This can also happen when/if MassLynx is not listed as an exclusion on any and all Anti-Virus software is running.  

    Have you already checked these things?

    Good Luck!