510
Not Extended!
Further extensions to the request are required for the server to fulfill it
Help for Endusers
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What could be the reason for this?
↓
The request is missing required extensions
What can I do about this?
↓
Use a compatible application
Help for Professionals
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Additiona error details
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What could be the reason for this?
↓
Mandatory extension declarations are missing in the request
What can I do about this?
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Include all required extension headers
