The support DLLs in PI for each probe model implement a ValidateSample() function that is called after an acquisition setup is edited. ValidateSample() performs instrument specific sanity checks on the acquisition setup. In the global INI there is a key called ValidateSample= that is by default set to 1 (perform the checks). If set to zero the checks are skipped (and a warning is printed in the log at start up). There is no GUI for this setting so you shouldn't see the log message unless someone is manually playing around in the INI file.
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