EXFO FTB-500 (Window XP) - Manual (Page 290)

Troubleshooting
280 FTB-500
Restoring Your Unit to Normal Operation
To verify disk integrity:
1. Turn on the FTB-500.
2. While the system is displaying the boot menu (3 seconds), press .
OR
Press any key on the keyboard (if you have connected one).
3. Press to select the emergency system tools operation mode, then
LOCAL to confirm your choice.
Note: The touchscreen becomes effective at this point.
4. From the main window, select Check disk integrity, then tap Next.