Encrypting a workbook

Aspose.Cells Product Family
1

As far as I am aware, Aspose.Excel does not support encrypting/protecting a workbook (Tools -> Options -> Security -> Password to Open. Are there any plans to add this feature?

2

Yes. Encrypting a workbook is not supported now. We will investigate this issue but we don’t have a specific plan.

3

@jgalun,
Aspose.Cells has replaced Aspose.Excel which is no more continued now and discarded now. This new product contains all the features which were supported by Aspose.Excel as well as the latest features of MS Excel. You can encrypt excel file using Aspose.Cells as demonstrated in the following sample code:

// For complete examples and data files, please go to https://github.com/aspose-cells/Aspose.Cells-for-.NET
// The path to the documents directory.
string dataDir = RunExamples.GetDataDir(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

// Instantiate a Workbook object.
// Open an excel file.
Workbook workbook = new Workbook(dataDir + "Book1.xls");

// Specify XOR encryption type.
workbook.SetEncryptionOptions(EncryptionType.XOR, 40);

// Specify Strong Encryption type (RC4,Microsoft Strong Cryptographic Provider).
workbook.SetEncryptionOptions(EncryptionType.StrongCryptographicProvider, 128);

// Password protect the file.
workbook.Settings.Password = "1234";

// Save the excel file.
workbook.Save(dataDir + "encryptedBook1.out.xls");

Following article provides detailed information about encrypting the Excel file, specifying password to modify option and verifying the password of the encrypted file.
Encrypting Excel Files

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