Fail Fast Exception C0000409

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A Fail Fast Exception is a type of Exception made by User Mode applications.

The Exception Code is 0xC0000409 (a.k.a. STATUS_FAIL_FAST_EXCEPTION).

The first Exception Parameter (0) defines the Sub-Code. Some sub-codes use additional Exception Parameters to specify additional detail.

Unlike all other exception codes, Fail Fast Exceptions bypass all exception handlers (frame or vector based). Raising this exception terminates the application and invokes Windows Error Reporting, if Windows Error Reporting is enabled.

The Exception Code was initially designed to raise a security check failure. Specifically, Guard Segment (/GS) violations. Over time, the desire to have an immediate termination ability was leveraged by applications for non-security reasons. These applications leverage the first parameter to specify the scenario (a sub-code). The original "security check failure" use-case is reserved with a value of 0.

The Exception Parameter values are currently not defined due to the per-application nature.

The .exr and !analyze commands of the Debugger Tools for Windows provide a description when possible.

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The Discussion

  • User profile image

    Is bugcheck 0x139 the kernel mode cousin of this exception? The 0x139 documentation seems remarkably similar to what was discussed in this episode.

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