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If you need move spaces, simply hit Save. The page will refresh and additional URLs will be possible.
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Using the existing site's sitemap file to make sure everything redirects properly.
In this tutorial we will use the Migration Check Tool located on this page to make sure we have everything mapped properly. The first thing we need to do is enter the URL for our existing site's sitemap as shown below and then click generate report.
The system will download the sitemap and then generate a Excel report file. While the report is generating your screen will show a progress bar.
Once the report has been generated it will download to your machine. Open the Excel document.
For each URL that is a 404 error you should create a From -> To URI mapping with the send Permanent Redirect Option.