Resolve the 0xe4020045 unsupported client error in onenote

You may see the 0xE4020045 error code in OneNote 2016 or 2013 after clicking a yellow Info Bar that appears when a locally stored notebook was dragged (or otherwise added) to OneDrive for the purpose of backing it up, syncing it, or sharing it. While this may give the appearance that the notebook is now a cloud-based notebook, OneNote will continue to treat it as a locally stored notebook unless the notebook is properly moved to OneDrive.

You can try to resolve this issue by doing the following:

1. Exit OneNote, if it is still running.

2. On your computer's hard drive, navigate to the folder in which the affected notebook is stored.

   Tip: Typically, the default location for locally stored OneNote for Windows notebook folders is C:\Users\<username>\Documents\OneNote Notebooks.

3. Copy the folder with the same name as the affected notebook to the root folder of your main hard drive.

   Doing this effectively removes the copy of the notebook out of OneDrive's sync scope.

4. In Windows File Explorer, click This PC, double-click to open the hard drive root location to which you just copied the notebook in the previous step, and then double-click the folder with the name of the copied notebook.

5. In the copied notebook folder, double-click the Open Notebook.onetoc2 file.

   If this file is not present, double-click any other available *.onetoc2 file in this folder.

6. When OneNote 2016 for Windows opens, the notes from the copied notebook folder should now be displayed properly.

To prevent this issue from happening again, we strongly recommend that you follow the required procedure for properly moving the original affected notebook to your OneDrive account, which will convert it from a locally stored notebook to a true cloud-based notebook. Your cloud-based notes will still be private, but you'll enjoy more reliable syncing and you'll be able to access your notes from any mobile device or any Web browser that you use.

For more information, see Move a OneNote for Windows notebook to OneDrive. The instructions in this article also apply if you're using older versions of OneNote for Windows, such as OneNote 2013 or 2010.