Countersign Method
Countersigns an existing signature.
Syntax
int Countersign();
Remarks
Use this method to certify an existing document signature. Countersigning doesn't alter the existing signatures or the signed document itself.
Error Handling
This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)