Bypass IO / Direct Storage is not working for any games

For some reason none of my games that use DirectStorage fail, including the Microsoft BulkLoadDemo with the following error:

File System Filter 'atc' (Version 10.0, ‎2023‎-‎12‎-‎11T18:22:43.000000000Z) vetoed bypass IO.

     Process: BulkLoadDemo.e

     File: M:\Direct Storage benchmark 1.2\Release\Output\BulkLoadDemo\Avocado.marc

     Bypass IO Operation: FS_BPIO_OP_ENABLE

     Vetoing Reason: Not allowed for requesting application.

     Operation Status: {Access Denied}

A process has requested access to an object, but has not been granted those access rights.

I assume that the that 'atc' filter is Bitdefender because of the atc.sys file in Windows/System32/Drivers?

My system is fully supports DirectStorage, so the hardware is not an issue. Does Bitdefedner not support BypassIO? If not how can I temporarily disable the Bitdefender atc filter?


  • thegilpins
    thegilpins ✭✭✭

    I think I have resolved this by adding an exception for the relevant games into Advanced Threat Defence and I now no longer get the error messages.

    Will Active Threat Defence be updated to support BypassIO in the near future?

  • Hello @thegilpins,

    Yes, Advanced Threat Defense is a Bitdefender feature that continuously monitors running processes to identify anomalies in apps behavior and correlates different suspicious behaviors to significantly improve detection. This method is different from traditional malware detection, which involves identifying malware using the virus signature database. Check out this Bitdefender Advanced Threat Defense Overview to learn more.

    Adding an exception in your case should do the trick. Regarding BypassIO & security solutions, I did find an older discussion about this on Reddit, check it out:

    I think you can ask this question to the Bitdefender Support teams and they can check with the product developers for more insights. Feel free to refer them to this thread and the Reddit posts, for more context. You can reach them using the link below:

    State your contact reason, then choose from the available contact channels, chat, phone and email/ticket. Chat would be the fastest way to reach them.

    I hope the information is helpful.



    Premium Security & Bitdefender Endpoint Security Tools user