Temporary change to file size download limit in OneNote
Summary
To best support OneNote customers worldwide during these unprecedented times, Microsoft is temporarily adjusting the download limit of file attachments in OneNote. We do not expect this change to affect most users.
Workarounds
The maximum capacity of downloaded file attachments is temporarily set at 100 MB. Because most OneNote clients limit file uploads to 50 MB, this change shouldn't affect most attachments.
The following workarounds enable users to download larger file attachments:
Attach as a cloud file. This is the best way to make sure that others can access the file without restrictions. If you have access to the file, first upload the attachment to SharePoint Online and then link to the attachment from within the Notebook. If you use OneNote for Windows 10, this can be done in one step by following these instructions:
1. Select Insert > File.
2. Select Upload to OneDrive and insert link.
Attaching files as cloud files enables others who have access to the notebook to view your attachment without any size restrictions. If you don't have access to the original file, use either of the following workarounds to obtain the file, and then attach it as a cloud file.OneNote for web. Open your notebook in OneNote for the web (go to https://www.onenote.com, select the purple Sign in button), and then save the attachment by right-clicking the attached file and selecting Save As.
OneNote desktop. Use OneNote 2016 or another desktop version of OneNote to download the attachment.
More information
Still need help? Go to Microsoft Community.