WSA_QOS_EPSFLOWSPEC - 11027 (0x2B13)
An invalid or inconsistent flowspec was found in the QOS provider specific buffer.
Updated: Feb 21, 2026
Technical Meaning
The error code WSA_QOS_EPSFLOWSPEC (11027, 0x2B13) indicates that the Quality of Service (QoS) provider specific buffer contains an invalid or inconsistent flowspec. Flowspec is a mechanism used to control network traffic based on certain criteria such as bandwidth, latency, and jitter.
Error Details
This error typically occurs when the QoS API encounters issues with the flowspec data provided by the application or system. The QoS provider specific buffer is where this information is stored and processed. If the data in this buffer does not meet the expected format or criteria, the error WSA_QOS_EPSFLOWSPEC is generated.
Usage Context
This error can occur in various scenarios involving network traffic management through the QoS API. It may be encountered when setting up or modifying QoS policies for applications or services that require specific network behavior.
Developer Interpretation
Developers should interpret this error as an indication that there is a problem with the flowspec data being passed to the QoS provider. This could mean incorrect parameter values, invalid object types, or exceeding certain limits. Developers must ensure that all parameters and data structures are correctly formatted before calling functions related to QoS.
Related Errors
WSA_QOS_INVALID_PARAMETER(10022, 0x2746): An invalid parameter was passed to the function.WSA_QOS_NETWORK_NOT_AVAILABLE(10053, 0x279D): The network is not available for QoS operations.
FAQ
What does WSA_QOS_EPSFLOWSPEC mean?
This error indicates that an invalid or inconsistent flowspec was found in the QoS provider specific buffer. It suggests a problem with the data passed to the QoS API.
How can I resolve this issue?
Ensure that all parameters and data structures are correctly formatted before calling functions related to QoS. Verify the correctness of the flowspec data being provided.
Summary
The WSA_QOS_EPSFLOWSPEC error (11027, 0x2B13) is a specific technical issue encountered when working with Quality of Service APIs in Windows. It highlights problems with the flowspec data passed to the QoS provider and requires careful validation and formatting of input parameters.