If you encounter the following error (An Error Occurred when trying to upload ASN Items Error Message: The conversion cannot be performed.) while attempting to upload items to an ASN please check the CSV file as it could contain non-numeric data in numeric fields, this can include spaces as well as characters which are non-numeric.
Examples of incorrect data in fields
SKU: (Blank) instead of SKU-123
Quantity: One instead of 1
Height: 10cm instead of 10