T999 Error on Update Agent for Bully Dog GT Tuner

    November 17th, 2021

    If your Tuner for a Toyota gets a T999 Update Agent Error it means that there is a connection issue with the update agent to our server. 

    Verify any Anti-Virus programs are off, or disabled and continue to retry the update until the server reconnects and allows an update. (If you are unsure how to disable your Anti-Virus program please refer to your user manual for that software. 

    If the problem persists, please contact our Technical Support Team using the "Contact Support" button below. Please be sure to have your device and access to a PC computer with internet access.

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