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On the batch item export screen make sure to select "Google Product Search Columns" as the Export Contents as shown below.
This will download a spreadsheet file that has the item ID, description and all the Google Product Search columns. The spreadsheet should appear in your Excel and look like the screenshot below.
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The first step is to click browse and locate the file on your computer. Then click Continue as shown in the screenshot below.
The batch item import utility is smart enough to identify the Google Product Search spreadsheet and automatically map all the columns out as shown below.
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