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# CMTagCollectionError

Error codes returned by Core Media when working with tag collections.

```
enum CMTagCollectionError : OSStatus;
```

## Topics

### Tag Collection Error Codes

[`kCMTagCollectionError_AllocationFailed`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_AllocationFailed)

Indicates an internal allocation failed.

[`kCMTagCollectionError_ExhaustedBufferSize`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_ExhaustedBufferSize)

Indicates that a buffer was smaller than the number of requested tags.

[`kCMTagCollectionError_InvalidTag`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_InvalidTag)

Indicates that the collection contains an invalid tag.

[`kCMTagCollectionError_InvalidTagCollectionData`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_InvalidTagCollectionData)

Indicates that a Core Foundation data instance failed to initialize a new tag collection.

[`kCMTagCollectionError_InvalidTagCollectionDataVersion`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_InvalidTagCollectionDataVersion)

Indicates that a Core Foundation data instance failed to initialize a new tag collection due to a versioning problem.

[`kCMTagCollectionError_InvalidTagCollectionDictionary`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_InvalidTagCollectionDictionary)

Indicates that a Core Foundation dictionary instance failed to initialize a new tag collection.

[`kCMTagCollectionError_ParamErr`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_ParamErr)

Indicates a parameter to a function was of the wrong type or didn’t meet a necessary condition.

[`kCMTagCollectionError_TagNotFound`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_TagNotFound)

Indicates that there was no match in a collection for a tag.

[`kCMTagCollectionError_InternalError`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_InternalError)

Indicates an error occurred inside of the Core Media framework.

### Constants

[`kCMTagCollectionError_NotYetImplemented`](/documentation/CoreMedia/CMTagCollectionError/kCMTagCollectionError_NotYetImplemented)

Indicates a function lacks a necessary backing implementation in Core Media.


---

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