The Post Processing part of an Excel report in the Dashboard is the same as writing the code directly in Excel to interface to the OTA API. Very similar to writing your own program, and limited to the scripting language available in Excel.
Since the post processing is executed after Excel is opened, and Excel is opened locally for whomever runs the report, then that person would need to have the necessary components installed on their system for interfacing to the OTA API I think. That would mean registering the QC client on that workstation.
I have not actually written anything in post processing for an Excel Dashboard report, or directly in Excel to interface to the OTA API. I expect it can be done, I just haven't ever had a reason to try.
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