Removes all digital signature permissions from the PDF document.
public void RemoveSignaturePermissions()
Saving documents in the non-incremental (default) mode invalidates all existing signature permissions. Therefore, we recommend removing existing signature permissions before saving. Or you can write incrementally (see the WriteIncrementally property).
PDF viewers might limit allowed operations for a document with invalid signature permissions. For example, Adobe Reader shows a warning like "This document enabled extended features in Adobe Acrobat Reader. The document has been changed since it was created and use of extended features is no longer available. Please contact the author for the original version of this document" and disables form filling.
Use the HasSignaturePermissions property to check if the document has digital signature permissions.
If you set the RemoveSignaturePermissions option in the save options to true, then the library will remove the permissions automatically before saving the document.