Sometimes, though fortunately extremely rarely, OneDrive can become corrupt and stop syncing your files and documents to the cloud. This usually happens because essential configuration files have become corrupt. It’s a simple problem to fix however. Firstly, open OneDrive from its icon in the system tray, click the More option and Quit OneDrive to shut it down. 
Next open File Explorer and in the View tab on the Ribbon check the Hidden items option. You will want to uncheck this when you’re finished. In the This PC view open the drive on which Windows 10 is installed and navigate to Users > [YourUserName] > AppData > Local > Microsoft > OneDrive. 
Once in the OneDrive folder you will see three folders called logs, settings and setup. Highlight these folders and delete them. DO NOT delete anything else or OneDrive will fail to work. 
With this done, start OneDrive again by searching for it in the Start Menu. You will be prompted to sign in using your Microsoft or Azure AD account, and then choose your configuration options, such as where on your hard disk your OneDrive files are stored. OneDrive will now operate normally.
For in-depth Windows 10 Troubleshooting advice, Mike Halsey’s book “Windows 10 Troubleshooting, Second Edition” is on sale now from Apress, Amazon, and all good booksellers.
