I search the source code of itext-src2.0.6 and iTextSharp-4.0.7 with the keyword “PdfReader not opened with owner password”, and get the following result,
itext-src-2.0.6
[F:\soft\0710\itext\itext-src-2.0.6\com\lowagie\text\pdf\PdfCopyFieldsImp.java]
Line 115 : throw new IllegalArgumentException(“PdfReader not opened with owner password”);
[F:\soft\0710\itext\itext-src-2.0.6\com\lowagie\text\pdf\PdfReaderInstance.java]
Line 85 : throw new IllegalArgumentException(“PdfReader not opened with owner password”);
[F:\soft\0710\itext\itext-src-2.0.6\com\lowagie\text\pdf\PdfStamperImp.java]
Line 103 : throw new IllegalArgumentException(“PdfReader not opened with owner password”);
itextsharp-4.0.7
F:\soft\0712\itextsharp-4.0.7\iTextSharp\text\pdf\PdfCopyFieldsImp.cs(102): throw new ArgumentException(“PdfReader not opened with owner password”);
F:\soft\0712\itextsharp-4.0.7\iTextSharp\text\pdf\PdfReaderInstance.cs(86): throw new ArgumentException(“PdfReader not opened with owner password”);
F:\soft\0712\itextsharp-4.0.7\iTextSharp\text\pdf\PdfStamperImp.cs(92): throw new ArgumentException(“PdfReader not opened with owner password”);