In my application I wrote this function. It works. Change it for your needs:
Private Sub cmdFormate_Click()
Dim oXL As Excel.Application
Dim tempstr As String
' Start Excel and get Application object.
Set oXL = New Excel.Application
oXL.Visible = False
oXL.DisplayAlerts = False
oXL.Workbooks.Open FileName:= _
txtExcelDoc
oXL.ActiveWorkbook.SaveAs FileName:= _
"C:\temp\temp.csv", FileFormat:= _
xlCSV, CreateBackup:=False
oXL.ActiveWorkbook.Close
CleanFile ("C:\temp\temp.csv"
oXL.Workbooks.Open FileName:="C:\Temp\2.csv"
oXL.Selection.AutoFormat Format:=xlRangeAutoFormatList3, Number:=True, Font:= _
True, Alignment:=True, Border:=True, Pattern:=True, Width:=True
oXL.ActiveWorkbook.SaveAs FileName:="C:\Temp\TitlePTO_" & Replace(Replace(Now, "/", ""

, ":", ""

& ".xls", FileFormat:=xlExcel9795, _
Password:="", WriteResPassword:="", ReadOnlyRecommended:=False, _
CreateBackup:=False
oXL.ActiveWorkbook.Close
oXL.Quit
Set oXL = Nothing
Dim fso, MyFile
Set fso = CreateObject("Scripting.FileSystemObject"

Set MyFile = fso.GetFile("C:\temp\1.csv"

MyFile.Delete
Set MyFile = fso.GetFile("C:\temp\2.csv"

MyFile.Delete
Set MyFile = fso.GetFile("C:\temp\temp.csv"

MyFile.Delete
Set fso = Nothing
RecName = tempstr1
MsgBox "Done"
End Sub