BUG: "Old format or invalid type library" error when automating Excel (320369)

CAUSE

You receive this error calling an Excel method when the following are true:

The method requires an LCID (locale identifier).
You run an English version of Excel but the regional settings for the computer are configured for a non-English language.

If the client computer runs the English version of Microsoft Excel and the locale for the current user is configured for a language other than English, Excel will try to locate the language pack for the configured language. If the language pack is not found, the error is reported.

WORKAROUND

To work around this problem, you can:

Install the Multilingual User Interface Pack for your version of Office.

Or, execute the Excel method or property using InvokeMember so that you can specify the CultureInfo for the call. For example, the following code illustrates how you can invoke the Workbooks object Add method with "en-US" as the CultureInfo:

Dim oApp As New Excel.Application()
oApp.Visible = True
oApp.UserControl = True
Dim oBooks As Object = oApp.Workbooks
Dim ci As System.Globalization.CultureInfo = New System.Globalization.CultureInfo("en-US")
oBooks.GetType().InvokeMember("Add", Reflection.BindingFlags.InvokeMethod, Nothing, oBooks, Nothing, ci)

Or, set the CultureInfo prior to calling the Excel method. For example:

Dim oApp As New Excel.Application()
oApp.Visible = True
oApp.UserControl = True
Dim oldCI As System.Globalization.CultureInfo = _
    System.Threading.Thread.CurrentThread.CurrentCulture
System.Threading.Thread.CurrentThread.CurrentCulture = _
    New System.Globalization.CultureInfo("en-US")
oApp.Workbooks.Add()
System.Threading.Thread.CurrentThread.CurrentCulture = oldCI

When you use one of these workarounds for a computer where the regional settings do not match the current language version of Office, you should be familiar with how Excel behaves and how Excel will interpret data that might be formatted for a specific locale. For more details about writing globalized Excel solutions with Visual Studio .NET, please see the following articles in the MSDN:

Creating Office Solutions for Use in Multiple Countries/Regions
http://msdn.microsoft.com/library/en-us/odc_vsto2003_ta/html/odc_VSTMultCR.asp

Globalization and Localization Issues for Solutions Created with Microsoft Visual Studio Tools for the Microsoft Office System
http://msdn.microsoft.com/library/en-us/odc_vsto2003_ta/html/VSTO_globalization.asp

MORE INFORMATION

Steps to Reproduce the Behavior

Verify that the locale for the computer is set to a language other than English.

For Windows 2000:
1. In Windows Control Panel, double-click Regional Options.
2. On the General tab, select a location, and then click OK.
For Windows XP or Windows Server 2003:
1. In Windows Control Panel, double-click Regional and Language Options.
2. On the Regional Options tab, select a locale, and then click OK.
Start Microsoft Visual Studio .NET.
On the File menu, point to New, and then click Project. In the New Project dialog box, under Project Types, click Visual Basic Projects. Under Templates, click Windows Application, and then click OK. By default, Form1 is created.
On the View menu, click Toolbox, and then add a button to Form1.
To display the code window for the form, double-click Button1.

In the code window, replace the following code

Private Sub Button1_Click(ByVal sender As System.Object, _
                          ByVal e As System.EventArgs) _
                          Handles Button1.Click
End Sub

with:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Dim oApp As Object
    Dim oDoc As Object
    oApp = CreateObject("Excel.Application")
    oApp.Visible = True
    oDoc = oApp.Workbooks.Add
    oDoc.Close()
    oApp.Quit()
    oDoc = Nothing
    oApp = Nothing
End Sub

Add the following line to the beginning of the Form1 code module:
```
Option Strict Off
```
Press F5 to build and run the program.
To generate the error, click Button1. The error occurs on the line that reads:
```
oDoc = oApp.Workbooks.Add
					
```

REFERENCES

For more information on Office Automation, visit the following Microsoft Office Development Web site:

http://support.microsoft.com/ofd

For information about the Office XP Multilingual User Interface Pack, see:

Availability of Office XP with Multilingual User Interface Pack
http://www.microsoft.com/office/evaluation/indepth/multilingual/muipackavailable.asp

Additionally, see the following Microsoft Knowledge Base articles:

301982 HOWTO: Automate Microsoft Excel from Visual Basic .NET

302084 HOWTO: Automate Microsoft Excel from Visual C# .NET