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Can I specify a new SKU in my Multi-Variation item with a quantity set to 0 when I list or relist an item?
No, if you select inventory tracking method to SKU, on a multi-variation item, you must specify SKU's with only a quantity of 1 or greater. Specifying 0 quantity would result in the following warning to be returned.
Variations with quantity '0' will be removed.
To avoid the warning only add new SKU's when you have quantity specifed greater than 1.
It is ok to change the quantity to 0 in subsequent ReviseFixedPriceItem requests when neccessary.
When can I specify quantity as 0 for a new variation?