In older versions of the T.O.V.A. software, you may encounter errors communicating with the T.O.V.A. USB device:

• com.tovatest.usbd.USBDErrorException: Unknown stimulus event type used in session event list
• com.tovatest.usbd.USBDCRCException: Checksum not valid

If you have not already, update to the latest T.O.V.A. software.

• Please restart the TOVA software and/or re-attach the T.O.V.A. device to a different USB port.
• Make sure you have the T.O.V.A. hardware connected to a USB port on the PC not a USB hub.
• Unplug any other USB devices (printers, webcams, etc.), at least temporarily. Sometimes other devices can create noise that interrupts communication.
• Restart your PC.

If after trying these, you are still having problems, please follow these instructions:

1. Open the T.O.V.A. program.
2. Click ‘Preferences’.
3. Under ‘Logging Options’, change ‘Hardware log level’ from ‘WARN’ to ‘DEBUG’.
4. Click ‘Save’.

After you enable hardware debug logging, launch a new session. If you continue to get the same error (or any other issue), please send a technical support request through your program. The logging changes above will tell us more about the problem and assist us in resolving your issue.