RSS error

I don't use RSS feeds myself, but maybe this will help:
Unsubscribe from an RSS Feed - Outlook - Microsoft Office

When you cancel or unsubscribe from an RSS Feed, no new content is downloaded. You can choose whether to delete or keep all the content that was downloaded from the RSS Feed.

Unsubscribe and delete all content

1. In Mail, in the Navigation Pane, expand the RSS Feeds folder.
2. Select the folder for the RSS Feed, and then press DELETE.
3. When prompted to confirm the deletion, click Yes.

Unsubscribe and keep downloaded content

1. Click the File tab.
2. Click Account Settings, and then click Account Settings.

1. On the RSS Feeds tab, under Feed Name, click the RSS Feed, and then click Remove.

Note To cancel multiple RSS Feeds, press and hold CTRL as you click RSS Feed names.

1. When prompted to confirm the deletion, click Yes.

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ALSO: Some additional information on RSS feeds:
Read RSS Feeds - Outlook - Microsoft Office

SeamanV said:

Thank you for your help. I have got rid of that nagging pop up. You're da man!

Well done, SeamanV!