What does HRESULT 0xC0AA0403 (E_IMAPI_DF2DATA_STREAM_NOT_SUPPORTED) mean?

E_IMAPI_DF2DATA_STREAM_NOT_SUPPORTED

E_IMAPI_DF2DATA_STREAM_NOT_SUPPORTED identifies a source-stream problem in the data writer. Microsoft documents a concrete Write requirement: the stream size must be a multiple of the 2048-byte sector size, including ISO streams that were not created by IMAPI.

Validate the IStream contract before touching the disc

• Obtain the stream size and verify size % 2048 == 0.
• Seek and read the same IStream through the application path before passing it to Write.
• Record whether the image came from IFileSystemImageResult::ImageStream or an external ISO/image producer.

This differs from E_IMAPI_DF2DATA_STREAM_TOO_LARGE_FOR_CURRENT_MEDIA. A stream can be sector-aligned and structurally acceptable yet exceed available capacity; conversely, a small stream can fail the format contract. Padding arbitrary malformed content to a 2048-byte boundary is not a substitute for producing the intended disc image, but checking alignment is the first documented invariant for this API.

Write · IDiscFormat2Data · IMAPI return values