PLEASE NOTE: eBay errors are common. If your item is receiving an eBay Error when trying to list, you can learn more by clicking "Read error message" to see what eBay is asking from your listing.
JoeLister tries to parse UPCs when required, but sometimes this process fails. In this case, click "List to eBay" on the item with the UPC error to bring up the pop-up listing tool. Next, find the "Item Specific" section. Set the "Dimension" to "UPC." Then, set the "Value" to the UPC of the item, if applicable. If you cannot find the UPC or continue to run into this same error while listing the item, enter "Does Not Apply" in the value, instead, as shown below. 
Ensure that your UPCs are valid. There are 3rd party tools available online that you may use for validation. If your number is an EAN, then it must be converted to an UPC. You may also enter "Does Not Apply" as the UPC or EAN value within the Item Details for some eBay categories.
Please see this article about similar UPC and EAN eBay error and how to resolve.