ERROR_EVT_FILTER_UNEXPECTEDTOKEN - 15021 (0x3AAD)
The token encountered was unexpected.
Updated: Feb 21, 2026
Technical Meaning
The ERROR_EVT_FILTER_UNEXPECTEDTOKEN error code indicates that an unexpected token was encountered during event filtering. This typically occurs when the system is processing events and encounters a token that does not conform to the expected format or structure.
Error Details
This error can arise in various scenarios where event filtering mechanisms are employed, such as in Windows Event Log filtering or custom logging systems that rely on specific token structures for parsing and filtering events. The unexpected token could be related to metadata, tags, or any other structured data used within the event.
Usage Context
This error is relevant in contexts involving event processing and filtering, particularly where custom event formats are defined and expected tokens are part of the structure. It can occur when integrating third-party logging solutions or custom event handling mechanisms that rely on specific tokenization rules.
Developer Interpretation
When encountering this error, developers should review the event data being processed to ensure it adheres to the expected format. This includes checking for any discrepancies in metadata, tags, or other structured elements within the events. Ensuring consistency and correctness of input data is crucial to avoid such errors.
Related Errors
ERROR_EVT_INVALID_QUERY(0x8024301C): Indicates an invalid query was used during event filtering.ERROR_EVT_FILTER_TOO_COMPLEX(0x80243025): Suggests the filter expression is too complex or not supported.
FAQ
Q: What does ERROR_EVT_FILTER_UNEXPECTEDTOKEN mean?
A: It indicates an unexpected token was encountered during event filtering, suggesting a mismatch in expected and actual data structures.
Q: How can I resolve this error?
A: Review the input data for events to ensure it conforms to the expected format. Verify that all tokens used are correctly defined and match the expected structure.
Summary
The ERROR_EVT_FILTER_UNEXPECTEDTOKEN error signifies an unexpected token during event filtering, which is a generic issue related to data validation and consistency in event processing systems. Developers should focus on ensuring input data adheres to the specified format to prevent such errors.