You can sync up to 20,000 items total across all synchronized libraries

You can sync up to 5,000 items in a SharePoint library

In SharePoint Online, file names can have up to 256 characters.

Folder names can have up to 250 characters.

Folder name and file name combinations can have up to 250 characters.

File size lime 2 GB (10 GB for consumer version)

https://support.microsoft.com/en-us/kb/2933738

1. Open Command Prompt in Administrator mode: Right-click on the Windows icon in the taskbar and select Command Prompt (Admin).

2. Type in taskkill /f /im OneDrive.exe to terminate any OneDrive processes and hit Enter.

3. Then type in either %SystemRoot%\System32\OneDriveSetup.exe /uninstall if you’re using 32-bit Windows 10 or %SystemRoot%\SysWOW64\OneDriveSetup.exe /uninstall if you’re using 64-bit Windows 10 and hit Enter

If you want to reinstall

4.  go to %SystemRoot%\SysWOW64\” folder in File Explorer and run the OneDriveSetup.exe program.

1. Press Win+R and type regedit to open up the Registry Editor

2. Navigate to the HKEY_CLASSES_ROOT\CLSID\{018D5C66-4533-4307-9B53-224DE2ED1FE6} registry key.

3. Double-click on System.IsPinnedToNameSpaceTree change its value from 1 to 0.

4. Log off or restart your computer. When you open File Explorer, the OneDrive entry should be gone from the list.