It is important to ensure that your OneDrive sync client is working properly so that you don’t lose data, or don’t have access to the latest version of a file when you need it most.
The best way to tell if the syncing is still working is to update a file in the OneDrive folder on your computer, then look at the OneDrive icon in your system tray - it's where the date and time are displayed. On a Windows computer, the system tray is typically located in the lower right corner of your screen; on a Macintosh computer, the system tray is typically located in the upper right corner of your screen.
If the OneDrive icon (two blue clouds) has an exclamation point on it, then there is an issue. You may need to expand the system tray by clicking on the carat icon (^) to see everything in the system tray – including the OneDrive icon. If there’s no exclamation point, then your syncing is working and there’s no need to do anything further.
Below is an example from a Windows computer showing a successfully up to date sync with OneDrive:
If your syncing isn’t working, It is possible, on a Windows computer, that the "Microsoft OneDrive" service has been "disabled".
To re-enable the Microsoft OneDrive service on your Windows computer, right-click an empty space on your Task Bar and select Task Manager. If you see a More Details button, click it. Click the Startup tab. Scroll down the list and select the Microsoft OneDrive service. If that service is Disabled click the Enable button. Exit the Task Manager. OneDrive should begin syncing. To confirm it is working, go through the steps above to tell if syncing is working.
On a Macintosh or Windows-based computer, if OneDrive is still not syncing, you may need to download the newest OneDrive client. To do this, logon to your email by going to https://o365.dartmouth.edu. Click the OneDrive app. Click the 
button. The window below will open and OneDrive will attempt to sync. If nothing happens, you should click the 'get the latest version of OneDrive' link in that window. Install the newest OneDrive client and follow the prompts.
In most cases, updating to the latest version of the OneDrive sync client resolves the issue. If you continue to have problems with this, please do not hesitate to contact your department's IT support office.