My vb.net program for Excel won't run on different computer - vb.net

Question

I wrote a vb.net program using Visual Studio 2010 Express to open and manipulate an Excel workbook. I have MS Office 2010 and my program works fine on my computer. When I try to run it on my wife's computer... nothing. I get no error messages... nothing. She has the same version of Office as I do, but she has Windows XP and I have Vista and her computer is has more security protocols than mine, but my other program, which does not import any Office namespaces, runs fine on her computer.
When I look at the task manager on her computer there is nothing under the Applications tab, but under the Processes tab I see an instance of Excel.exe, and if I try to run the program again, still nothing under applications, but yet another instance of Excel.exe under processes.
I have tried to install my program using the Click-Once technology and just the Release folder after a Rebuild... nothing.
I have also tried to compile it under versions 2.0, 3.0, etc.... nothing.
Here is some of the relevant code:
Public Class CleanUpDataForm
Dim m_objExcel As New Excel.Application
Dim m_rngRange, m_rngEnd As Excel.Range
Dim m_blnEntireRow, m_blnCancel As Boolean
Dim m_strRange, m_strSearch, m_strLogFrameCode As String
Const c_strCode As String = "log"
Friend Const c_intScrollBarWidth As Integer = 30
Private Sub CleanUpDataForm_FormClosed(sender As Object, e As System.Windows.Forms.FormClosedEventArgs) Handles Me.FormClosed
m_objExcel = Nothing
Dispose()
End Sub
Private Sub tsbOpen_Click(sender As System.Object, e As System.EventArgs) Handles tsbOpen.Click
ofdGetWorksheet.Title = "Select Worksheet"
ofdGetWorksheet.Filter = "All Excel Files (*.xl*)|*.xl*|(*.xlsx)|*.xlsx|(*.xlsm)|*.xlsm|(*.xlsb)|*.xlsb|(*.xlam)|*.xlam|(*.xltx)|*.xltx|(*.xltm)|*.xltm|(*.xls)|*.xls|(*.xla)|*.xla|(*.xlt)|*.xlt|(*.xlm)|*.xlm|(*.xlw)|*.xlw"
ofdGetWorksheet.FileName = ""
If ofdGetWorksheet.ShowDialog <> System.Windows.Forms.DialogResult.Cancel Then
Me.Text = ofdGetWorksheet.FileName
m_objExcel.Workbooks.Open(Me.Text)
tsbCopySheet.Enabled = True
tsbFindRows.Enabled = True
tsbClose.Enabled = True
m_objExcel.Visible = True
Else
Me.Text = ""
End If
Me.Activate()
End Sub
Any ideas??

Answer 1

I believe that I was having this issue as well, but this line of code (after your m_objExcel.visible statement) was what fixed it (going from memory).
m_objExcel.Windows(1).Visible = True
One thing you may want to look at is the Marshal.BindToMoniker method in the InteropServices library. I found this incredibly useful. If the file is not open, then it opens it. If it is open already, then it will use that instance. Like this...
wb = System.Runtime.InteropServices.Marshal.BindToMoniker(fileName) 'open the file. If the file is already open, then this uses the open file instead of trying to open again
exApp = wb.Parent
wb is my workbook variable, exApp is my Excel variable.
One other thing; to make sure Excel is closed and to remove those pesky processes from Task Manager
Private Sub KillExcel()
For Each RunningProcess In Process.GetProcessesByName("Excel")
RunningProcess.Kill()
Next
End Sub