Updates in SharePoint are overwritten during collaboration
The issue occurs when multiple users are collaborating on a file and one (or more) user is disconnected from the internet. Once the user is reconnected, the user either saves an updated version (i.e., updates to the previously opened version) or saves (or auto-saves) the previous version. This will overwrite any updates made by other user(s) while the user was disconnected.
Here’s an example that outlines the scenario:
User 1 opens the file and views current version A.
User 2 opens the same file and views current version A.
User 2’s internet is disconnected while viewing version A (e.g., due to spotty connection or the user closes the laptop). If the user updates the file while the internet is disconnect, the system shows that the upload is pending.
User 1 updates version A and saves it as version B.
User 2 does not see version B since his internet is disconnected.
User 2’s internet is reconnected and his version is saved as version C. This overwrites User 1’s updates made in version B.
Unfortunately in this scenario, User 2 does not receive an error so the user isn’t aware that the versions are out-of-sync when he saves the file or the system automatically saves the file (if auto-save is enabled).
The system should at a minimum alert the user that his version is out of sync with the version in SharePoint and not allow the user to overwrite the current version.