I am trying to encrypt PDF file. But after encryption when I open output file it has plain data instead of encryption data. I checked Encrypt call, it returned 1, EncryptStatus also returned 1, which shows encryption was success.

    DebenuPDFLibraryDLL1711 DPL("DebenuPDFLibraryDLL1711.dll");    DPL.LoadFromFile(L"2020news.pdf", L"");    int iNumPages = DPL.PageCount();    int EncPerm = DPL.EncodePermissions(1, 1, 1, 1, 1, 1, 1, 1);        //DPL.SetOrigin(1);    int ret = DPL.Encrypt(L"",L"", 3, EncPerm);    int st = DPL.EncryptionStatus();     if (ret != 1) {        int err = DPL.LastErrorCode();    }    // Attempt to save the file     if (DPL.SaveToFile(L"hello-world2.pdf") == 1)  {          // Display message that the 'Hello Word' file has been written successfully    }

What am I missing here? Why encryption data was not written to outputfile? I mimicked code from "Foxit Quick PDF Library 17 Developer Guide.pdf"