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Why does nothing happen after I click Remind me later on the New Version Notification window?

The manifest file generated by As of TCIA/NBIA 6.5.3 is now , manifest files are self-contained and only version 3.0 and later of TCIA the Downloader App can read it.   Please update your Downloader appApp.

Why, after I upgrade the Downloader App, do two versions of it appear in Apps & features on Windows 10, and on Programs and Features on Windows 7?

You can ignore the double entries. It is likely that you installed an early version of TCIA Downloader 2.0 or TCIA Downloader 1.0, both of which have different upgrade codes internally. The old software is removed when the new version is installed. If the newly installed app is not functioning as expected, you can manually remove the old app and reinstall the new app. However, it is not required to do so.

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