I have a problem in my desktop application. I am using VS.NET 1.1. I am using Word template to display the data. I have already include the reference of Interop.Word.dll, AxInterop.MSMask.dll, Interop.VBIDE.dll, Interop.Microsoft.Office.Core.dll, Interop.MSMask.dll in our application. When I click on the option it throw the following error: System.NullReferenceException: Object reference not set to an instance of an object. at Word.Documents.Open(Object& FileName, Object& ConfirmConversions, Object& ReadOnly, Object& AddToRecentFiles, Object& PasswordDocument, Object& PasswordTemplate, Object& Revert, Object& WritePasswordDocument, Object& WritePasswordTemplate, Object& Format, Object& Encoding, Object& Visible, Object& OpenAndRepair, Object& DocumentDirection, Object& NoEncodingDialog, Object& XMLTransform) at iMSW.frmMain.openTemplateFile(String fileName) in D:\Project\Astin\iMSW_Prj\Forms\frmMain.vb:line 1257 This error is occur when user is using the MSOFFICE 2000. But if user is using the MSOFFICE 2003 it’s working fine. Please help me. OTAsh