VB 2010 express trouble after project build automating excel - vb.net

Question

I am automating excel through vb2010 express. The project is working fine, but when I publish it, it is only working when the actual spreadsheet is open on the computer. If it isn't open, the ExecuteNonQuery functions errors out with no connection open even though it is coded to open on form load. What am I missing?
Thank you in advance,
Here is part of my code...
Public Class frmTrustDeposit
Dim cn As New OleDbConnection
Dim cm As New OleDbCommand
Dim da As OleDbDataAdapter
Dim dt As New DataTable
Private Sub frmTrustDeposit_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
cn.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=C:\Users\Beosma\Documents\HFH\pnTrustDeposits2015.xlsx;Extended Properties=Excel 8.0;"
cn.Open()
FillDataGridView("select * from [Sheet1$]")
End Sub
Private Sub FillDataGridView(ByVal Query As String)
da = New OleDbDataAdapter(Query, cn)
dt.Clear()
da.Fill(dt)
With DataGridView1
.DataSource = dt
.Columns(0).HeaderText = "PreNeed"
.Columns(1).HeaderText = "Buyer"
.Columns(2).HeaderText = "Beneficiary"
.Columns(3).HeaderText = "Date"
.Columns(4).HeaderText = "Payment"
.Columns(5).HeaderText = "Retained"
.Columns(6).HeaderText = "Deposit"
.Columns(1).AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill
End With
End Sub
Private Sub btnAdd_Click(sender As System.Object, e As System.EventArgs) Handles btnAdd.Click
Try
With cm
.Connection = cn
.CommandText = "insert into [Sheet1$]values('" & txtPreNeed.Text & "','" & txtBuyerName.Text & "', '" & txtBeneficiaryName.Text & "','" & txtDateReceived.Text & "', '" & txtPaymentAmount.Text & "', '" & txtRetainedAmount.Text & "', '" & txtDepositAmount.Text & "')"
.ExecuteNonQuery()
End With
FillDataGridView("select * from [Sheet1$]")
Catch ex As Exception
MsgBox(ex.Message, MsgBoxStyle.Critical, Text)
Return
End Try
MsgBox("Successfully updated!", MsgBoxStyle.Information, Text)
Call ClearTextBoxes(Me)
End Sub
End Class
Banana, what happens is when the excel sheet is not open, the datagrid fails to populate on load and the ExecuteNonQuery gets the error. If the sheet is open and I run the program, there are no errors at all.