Fileupload save to folder extension problems

[sirnose1]

I have some code that uploads a document, renames the file based on the the concat of the year and a users id. (ex. "2014-9806543210"). It should overwrite the file no matter what the extension, so it could be stored as "2014-9806543210.xls" "2014-9806543210.xlsx", "2014-9806543210.docx", etc. As long as the extension is the same, it will overwrite. I have been trying to use the wildcard ("*") to no avail. The following code does that:

Protected Sub OnConfirm(sender As Object, e As EventArgs)
Dim supplierCID = Session("CID")

fileName = fuProductCapsuleEXCEL.FileName.ToString
Dim newFileName As String = ""
Dim saveInfo As String
Dim ext As String = Path.GetExtension(fuProductCapsuleEXCEL.FileName).Substring(1)

salesYear = Request.QueryString("salesyear")

'If ext.Trim().ToLower() = "xls" Or ext.Trim().ToLower() = "xlsx" Then
saveInfo = "Original File Name: " & fileName & "<br/>"
saveInfo += "File Size: " & upload1.PostedFile.ContentLength / 1000 & " Kilobytes <br/>"
saveInfo += "Content Type: " & upload1.PostedFile.ContentType & "<br/>"
newFileName = salesYear + "-" + supplierCID + "." + ext
saveInfo += "New File Name: " + newFileName.ToString()
lblSaveInfo.Text = saveInfo
'check if file already exist
exist = CheckForDup(newFileName)
Dim confirmValue As String = Request.Form("confirm_value")

If exist.ToString() = True Then
If confirmValue = "Yes" Then
'save file
upload1.SaveAs(Application("IMARK_RootPath") & "/UPLOADED_FILE/G2G_SKUs/" + newFileName)
ClientScript.RegisterStartupScript(Me.[GetType](), "alert", "alert('File saved as " & newFileName & "')", True)
Else
'dont save file
ClientScript.RegisterStartupScript(Me.[GetType](), "alert", "alert('File saved as " & newFileName & "')", True)
End If
End If

If exist = False Then
upload1.SaveAs(Application("IMARK_RootPath") & "/UPLOADED_FILE/G2G_SKUs/" + newFileName)
ClientScript.RegisterStartupScript(Me.[GetType](), "alert", "alert('File saved as " & newFileName & "')", True)
End If
End Sub


Protected Function CheckForDup(ByVal newFileName As String) As Boolean

Dim supFldr As String = Application("IMARK_RootPath") & "/UPLOADED_FILE/G2G_SKUs/"
Dim savePath As String = Path.Combine(supFldr, newFileName)
exist = False

If File.Exists(savePath) Then
exist = True
Else
exist = False
End If

Return exist
Response.Write(exist)
Response.End()
End Function

I have code in another page that displays a hyperlink to the file if there is a file in the folder. It is set to just read .xlsx files because I don't know how to use other extensions for this problem. Your assistance would be greatly appreciated.

Thanks n advance