We recommend you to backup or sync your notes regularly, as crashes may happen, and deleting the app from your device will delete your data as well.
In case of trouble or when Nebo does not open anymore (after a Windows upgrade for instance), you can still access your .nebo notebooks this way:
Open the file explorer and enable the option to display hidden files.
You will then be able to find .nebo files in the following folder:
Save the content of the folder in another place on your computer to create a backup.
Note: You can also type '%appdata%' in the files explorer, it should help you find the hidden Nebo folder.
You will find a folder of 32 mixed letters and digits (or named '._noUser' if you have not signed in Nebo) that includes your .nebo files.
Warning: Deleting Nebo from your device will delete your notes as well.
For further investigation, please submit a ticket and add your .nebo files to your ticket, if you agree to share your notes. Please also add files from the "Notebook'sName-files" folder as they may help us troubleshoot.