What does Windows error code 14069 (ERROR_SXS_XML_E_BADXMLCASE) mean?

ERROR_SXS_XML_E_BADXMLCASE

ERROR_SXS_XML_E_BADXMLCASE (0x000036F5) is a Windows Side-by-Side XML parser status for application, assembly, policy, or configuration manifest processing.

XML reserves names beginning with case-insensitive forms of xml, and the XML declaration itself uses the lowercase target xml. A declaration written as <?XML ...?> or another case variant is not interchangeable with the required syntax.

XML rule involved

The XML recommendation reserves names matching the letters X, M, L in any case combination for standardization, while the declaration production is explicitly <?xml. This is a lexical parser error, not a Side-by-Side assembly-version conflict.

What to inspect

• Check the opening XML declaration for uppercase or mixed-case spelling of the xml token.
• Search generated processing-instruction targets and names for custom identifiers that begin with a reserved XML case variant.
• Correct the producer template so the invalid case is not recreated during the next build or package merge.

Capture one failing activation with sxstrace; the parser location distinguishes a bad declaration token from a later custom name that incorrectly uses the reserved prefix family.

References

• Microsoft: System Error Codes 12000-15999
• Microsoft: Side-by-Side manifest files reference
• Microsoft: sxstrace
• W3C: XML 1.0