OneDrive Not Syncing Due to Invalid Characters

Issue

When adding files to OneDrive for Business, a sync error appears.

Environment

This article applies to OneDrive for Business on Mac and Windows.

Cause

Certain special characters are not supported by OneDrive for Business, which will cause sync errors. These errors are indicated by a red "X" icon next to the file name. Below is a list of invalid characters:

• < (less than)
• > (greater than)
• : (colon)
• " (double quote)
• | (pipe)
• ? (question mark)
• * (asterisk)
• / (slash)
• \ (backslash)

In addition, file paths that are longer than 400 characters will not upload.

• Example of a valid file path on a Mac: /Users/username/Desktop/Pictures
• Example of a valid file path on Windows: C:\Users\username\Pictures

Resolution

Remove any invalid characters from the file names and paths:

Mac: Click the OneDrive icon located in the menu bar (top right of the screen), then select "View sync problems." A window will open with a list of invalid files. Click the magnifying glass to the right of a file name to open it in the Finder. Rename the file by double-clicking its name and pressing Return after making changes. Be careful to check for and remove any spaces at the beginning and end of the name.

Windows: Right-click on the OneDrive icon in the taskbar, then click "Tap or click for more info."

Select files and folders from the list that appears to remove any invalid characters.

After appropriately renaming a file, it should automatically upload within a few minutes. You may also find that there are files that don't seem to have any invalid characters. Those are usually located within a folder that has invalid characters. Once you change the folder name, all sync issues within the folder should be resolved.