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GroupDocs.Signature library can't add digital signature to dot, dotx, dotm and dos file


Hi GroupDocs.Signature team,

We used the latest GroupDocs.Signature for .NET API(trial license) to add Digital Signature to files, we found that:

  1. After we sign dot, dotx, ods, ots files, it can create a new file, but the new file doesn’t have the signature.
  2. When we sign dotm, it has an error “Signing feature is not support by this file format”, and the created file is 0KB.

According to your document, dot, dotx, ods, ots, dotm should be supported by the API, would you please help check it? Thanks.



Please provide us the following details so that we can investigate your reported issues at our end:

  • Sample files (it may also include the problematic output files) for which you are facing the issue.
  • The minimal source code that you are using to sign the documents.