¤
¤ I'm trying to automate excel from visual c#.  One thing I need to be able to
¤ test is if excel is even installed on the target machine and what version of
¤ excel is installed on the target machine.  Is there a way to do this via c#
¤ code?  

The following code should work but it depends upon correct registry entries for Excel. It's in
VB.NET but shouldn't be difficult to convert:

   Declare Function FindExecutable Lib "shell32.dll" Alias "FindExecutableA" (ByVal lpFile As
String, _
                                                                               ByVal lpDirectory As
String, _
                                                                               ByVal lpResult As
System.Text.StringBuilder) As Int32

  Function IsExcelInstalled(ByRef FileVersionMajor As String) As Boolean

       Dim DummyFile As String
       Dim FileDir As String
       'Const MAX_PATH As Integer = 255

       Dim FilePath As New System.Text.StringBuilder(255)
       DummyFile = "e:\My Documents\book1.xls"

       If FindExecutable(DummyFile, FileDir, FilePath) > 32 Then
           IsExcelInstalled = True
           FileVersionMajor =
System.Diagnostics.FileVersionInfo.GetVersionInfo(FilePath.ToString).FileMajorPart
       End If

   End Function

The alternative is to use Excel automation and catch any runtime errors.

  Function IsExcelInstalledAuto(ByRef FileVersion As String) As Boolean

       Dim ExcelObject As Object

       Try
           ExcelObject = CreateObject("Excel.Application")
           FileVersion = ExcelObject.Version
           ExcelObject.Quit()
           Return True
       Catch ex As Exception
           If ex.Message = "Cannot create ActiveX component." Then
               Return False
           Else
               Throw
           End If
       End Try

   End Function

Paul ~~~ pclement@ameritech.net
Microsoft MVP (Visual Basic)