The Microsoft Office Support team provides troubleshooting tips relating to naming, uploading and syncing files with OneDrive.
OneDrive has some rules about what characters can and cannot be in your file names. Certain characters are reserved for functions within Windows and SharePoint. When naming files in OneDrive, you should avoid using these special characters to ensure your file uploads properly.
Certain file types and extensions cannot be uploaded using OneDrive. Choose your version of OneDrive for a complete list of invalid file types and extensions.
Find file syncing tips for your operating system.