Board Thread:Questions and Answers/@comment-149.254.186.240-20131107184930/@comment-92.228.231.151-20140105125844

Get your inventory (ask the server adminstrator), download InvEdit and delete this item. You need its ID, just go into a singeplayer world.When you opened your inventory with INVEdit you'll see lots of purple circles with IDs (or something like this). Now search for the ID of this item and delete it. Then ask your server adminstrator for deleting the old file on the server and upload the new one. The simple way would be, clear the whole inventory.