A cloud-based task management app from Microsoft that helps users organize and manage daily tasks across devices.
Hi!
This error indicates a blockage during the authentication process. To help you better, please answer the questions below so I can gather more information:
On which operating system do you have To Do installed (Windows or Mac)?
Is your account a work/school account or a personal one?
Do other Microsoft apps on the same PC (such as Outlook, OneNote, Teams, or the Store) sign in successfully using this account? Please test this by trying to sign in to another Microsoft application that requires a login.