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The RelistFixedPriceItem call can be used to to relist fixed-price item that has ended. It is recommended to use this call instead of creating a new listing using the AddFixedPriceItem call to take advantage of the recent sales score associated with the listing.
Here is a VB.NET RelistFixedPriceItem sample for re-listing a multi-variation item; a variation from the original listing is deleted and a new variation is added during the relist operation. This sample has been written using the .NET SDK.
Below is the code. Corresponding SOAP request is attached with this article.
Public Class RelistFixedPriceItem