SecureBlackbox 16: When I open a signed document with Acrobat, it says that the 'EldoS.SecureBlackbox' handler used to create the signature could not be found. What should I do?

Note: This article applies only to SecureBlackbox Legacy. For future development please consider using the latest version.

Adobe Acrobat identifies the security handler that created the signature by its name. By default, SecureBlackbox creates signatures with the 'EldoS.SecureBlackbox' name. However, you can specify any name you like using the ElPDFPublicKeySecurityHandler.CustomName property.

Adobe Acrobat 'knows' two handler names:

  1. Adobe.PPKLite -- the signature is validated against certificates stored in the Acrobat certificate store.
  2. Adobe.PPKMS -- the signature is validated against certificates stored in the system (Windows) certificate store.

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