There is only one file type that uses the .TBS extension:
TuneUp Utilities Boot Screen
Image used for customizing the Windows boot screen with TuneUp Utilities; compressed using .ZIP compression to save disk space; may be modified using the TuneUp Styler (previously WinStyler) program included with TuneUp Utilities.
BootScreenView can be used to convert TBS files to .BOOTSKIN files.
Updated: March 26, 2010