This guide will walk you through a few things you can try when your OneDrive is not syncing.
Method 1: Restart the OneDrive App on your PC
Step 1:
Click Show hidden icons on the bottom right of your screen, then the OneDrive icon
Step 2:
When the OneDrive menu pops up, click the Settings Icon, then Quit OneDrive to exit
Step 3:
To start OneDrive again, click on the Search Icon, type OneDrive in the search box and select OneDrive to launch the app
Step 4:
Give it a few moments and then check to see if it is syncing now.
Method 2: Check if the file path is too long
According to Microsoft, the file path, including the file name, should not exceed 255 characters. So if the path of your file is too long, it can cause OneDrive not syncing.
An example of long file path:
C:\Users\shight\OneDrive\Documents\OfficeWork\2018\September\Deadline\ThisWeek\Wednesday\This_is_an_example_of_long_file_path.txt
You can try renaming the file with fewer characters, and also avoid having too many sub folders, inside of sub folders, to make the file path shorter.
Method 3: Check if there is any ~$ files in the directories
Your OneDrive not syncing issue might also be due to cache files (beginning with ~$ ) and the icon is faded in the OneDrive folder (see an example below).
If there is any, delete it and OneDrive should sync normally.