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These errors occur because the NBIA Data Retriever cannot work without with a manifest file. See Creating Manifest Files for instructions to create a manifest file using NBIA or an API. To avoid this error, first download and install the NBIA Data Retriever, then locate a manifest file on your computer. Finally, If you have not installed any versions of Downloader App or TCIA Downloader previously, you can just click on a manifest file and the NBIA Data Retriever will open correctly. If you have installed Downloader App or TCIA Downloader before, consider to remove these app first before installing NBIA Data Retriever but it is not mandatory, however you need to right-click the manifest file to choose to open it with the NBIA Data Retriever.
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