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[C# SDK] Box API v2: Chunked upload fails with "400 Bad Request - Digest Mismatch"

  • August 29, 2026
  • 0 replies
  • 6 views

We are currently working on a project where we use the Box C# SDK (v5.x) to upload large files (100MB+) to our Box Enterprise account using the Chunked Upload API (CreateUploadSessionAsync). While standard single-part uploads work flawlessly for smaller files, large chunked uploads fail consistently.

After creating the upload session and splitting the file into chunks, calls to UploadFilePartAsync return a 400 Bad Request (Digest Mismatch) response.

anyone help?