When you update branding settings, already-deployed desktop clients will not inherit these branding settings. It is for this reason that we recommend configuring branding settings before creating user accounts and deploying desktop clients.
Resolve with automatic updates
The next time already-deployed desktop clients are automatically updated, images defined by branding settings will display. However, paths and folder names will remain the same.
Note: You might need to restart the machine or kill and restart explorer for changes to be visible.
Need more information on branding settings?
For more details on custom branding, please review: Set Custom Branding