Hello, This error can sometimes occur when different versions of Excel are used on the different computers (2000 vs. XP, for instance). I would check the Excel Active Object that your Automation Refnum is attached to and make sure these objects are the same version on the two different machines.
Also do you know which Invoke Node or VI is throwing this error? Hope this helps! Let me know if there is anything else I can help with or clarify. Ken S. National Instruments
