This error message (visible in the Log Messages section) occurs when a location that is set up for ISO requesting in RACER, uses a Generic Script (GS) method to request - either via Amicus or the RACER online request form. There is no way to fix a request with this error, nor is there a way to action the request such that the borrowing library will see a message. You will not be able to indicate Shipped, Received, Message, Conditional, etc., instead the request stays at In Process / Check Error.
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