"Error reading cbColor.Style: The system cannot find the file specified" occurs when launching Toad. After clicking the "Ok" button, it gives multiple Access Violations and requires a kill session to get out of it.
Corrupted install files.
Completely uninstallToad and reinstall Toad.
For Toad v9.1 and below, please see solution 12846 for instructions.
For Toad v9.5 and above, please go to Start | All Programs | Quest Software | Quest Installer - go through the Quest Installer wizard to uninstall Toad.