If you see the error message "Upload Blocked" or are having trouble syncing Office files, the Office Upload cache system may be interfering with OneDrive sync. Try turning off the related setting in OneDrive settings.
Select the white or blue OneDrive cloud icon in the notification area, at the far right of the taskbar.
Note: You might need to click the Show hidden icons arrow next to the notification area to see the OneDrive icon. If the icon doesn't appear in the notification area, OneDrive might not be running. Select Start, type OneDrive in the search box, and then select OneDrive in the search results.
Select More > Settings.
Select the Office tab and uncheck the Use Office 2016 to sync Office files that I open check box.
Note: When you turn off the Use Office 2016 to sync Office files that I open setting, any changes that you and other people make to Office files in your OneDrive will no longer merge together automatically.