How to: Write-Protect a Workbook

Mar 29, 2021
2 minutes to read

Use the Workbook.DocumentSettings.WriteProtection property to return write-protection options for a document.

Make a Workbook Read-Only

Enable the WriteProtectionOptions.ReadOnlyRecommended option to make a workbook read-only.

C#
VB.NET

csharp

using(var workbook = new Workbook()) {
    var wpOptions = workbook.DocumentSettings.WriteProtection;
    wpOptions.ReadOnlyRecommended = true;
    workbook.SaveDocument("WriteProtectedDocument.xlsx");
}

Using workbook As New Workbook()
    Dim wpOptions As WriteProtectionOptions = workbook.DocumentSettings.WriteProtection
  wpOptions.ReadOnlyRecommended = True
    workbook.SaveDocument("WriteProtectedDocument.xlsx")
End Using

When users open this workbook in Microsoft® Excel®, it prompts them to open the document as read-only.

Specify a Password To Modify a Workbook

Call the WriteProtectionOptions.SetPassword method to specify a password to prevent modifications from unauthorized users.

C#
VB.NET

csharp

using(var workbook = new Workbook()) {
    var wpOptions = workbook.DocumentSettings.WriteProtection;
    wpOptions.SetPassword("Password");
    wpOptions.UserName = "John Smith";
    workbook.SaveDocument("WriteProtectedDocument.xlsx");
}

Using workbook As New Workbook()
    Dim wpOptions As WriteProtectionOptions = workbook.DocumentSettings.WriteProtection
    wpOptions.SetPassword("Password")
    wpOptions.UserName = "John Smith"
    workbook.SaveDocument("WriteProtectedDocument.xlsx")
End Using

When users open this workbook in Microsoft® Excel®, it prompts them to enter a password to modify the document.

Clear a Password Used to Modify a Workbook

The following code snippet uses the WriteProtectionOptions.CheckPassword method to check a given password. If the password is valid, WriteProtectionOptions.ClearPassword is called to remove write-protection from a workbook.

C#
VB.NET

csharp

using (Workbook workbook = new Workbook()) {
    workbook.LoadDocument("WriteProtectedDocument.xlsx");
    RemoveWriteProtection(workbook, "password");
}
// ...

private void RemoveWriteProtection(Workbook workbook, string password) {
    var wpOptions = workbook.DocumentSettings.WriteProtection;
    if (wpOptions.IsPasswordProtected && wpOptions.CheckPassword(password))
        wpOptions.ClearPassword();
    else {
        Console.WriteLine("The file is not write-protected or the specified password is invalid!");
        Console.ReadKey();
    }
}

Using workbook As New Workbook()
    workbook.LoadDocument("WriteProtectedDocument.xlsx")
    RemoveWriteProtection(workbook, "password")
End Using
' ...

Private Sub RemoveWriteProtection(workbook As Workbook, password As String)
    Dim wpOptions As WriteProtectionOptions = workbook.DocumentSettings.WriteProtection
    If wpOptions.IsPasswordProtected AndAlso wpOptions.CheckPassword(password) Then
        wpOptions.ClearPassword()
    Else
        Console.WriteLine("The file is not write-protected or the specified password is invalid!")
        Console.ReadKey()
    End If
End Sub