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  "title" : "Metadata Registry Error Codes"
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# Metadata Registry Error Codes

Error codes that indicate metadata registry errors.

## Topics

### Constants

[`var kCMMetadataDataTypeRegistryError_AllocationFailed: OSStatus`](/documentation/CoreMedia/kCMMetadataDataTypeRegistryError_AllocationFailed)

An error that indicates the allocation fails.

[`var kCMMetadataDataTypeRegistryError_BadDataTypeIdentifier: OSStatus`](/documentation/CoreMedia/kCMMetadataDataTypeRegistryError_BadDataTypeIdentifier)

An error that indicates a bad datatype identifier.

[`var kCMMetadataDataTypeRegistryError_DataTypeAlreadyRegistered: OSStatus`](/documentation/CoreMedia/kCMMetadataDataTypeRegistryError_DataTypeAlreadyRegistered)

An error that indicates the datatype is in a registered state.

[`var kCMMetadataDataTypeRegistryError_MultipleConformingBaseTypes: OSStatus`](/documentation/CoreMedia/kCMMetadataDataTypeRegistryError_MultipleConformingBaseTypes)

An error that indicates that type you provide has more than one base data type.

[`var kCMMetadataDataTypeRegistryError_RequiredParameterMissing: OSStatus`](/documentation/CoreMedia/kCMMetadataDataTypeRegistryError_RequiredParameterMissing)

An error that indicates a parameter the function requires is empty.

[`var kCMMetadataDataTypeRegistryError_RequiresConformingBaseType: OSStatus`](/documentation/CoreMedia/kCMMetadataDataTypeRegistryError_RequiresConformingBaseType)

An error that indicates the data type you specify requires a conforming data type that resolves to a base data type.


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