Save Workbook Of Imported Text Files As .xls

I am using the following code to import a number of text documents into the same workbook, on seperate sheets and then to save the workbook as an excel file. the problem is that when the file tries to save (red section) I get a message telling me that Excel can not save the workbook in the requested format, I think because it is still trying to save them as text files rather than as an excel workbook. When I try to save manually, selecting .xls as the format it works fine, but I would really like this to be part of the macro to ensure the WB is saved.

Sub ImportFiles()
Dim Sfile As String
Dim count As Integer
Dim ans As String
Dim A As Integer
Dim FileSaveName As String
count = 0
Application.DisplayAlerts = False
Do
' Allow user to select the file to open, text files only
Sfile = Application. GetOpenFilename("Text Files(*.txt), *.txt")
' Check that a file has been selected
If Sfile <> "False" Then......................