If i understand you well...
All what you need to do is to pass path to ms Access database as an argument:
Sub Mail_workbook_Outlook_2(ByVal sDatabaseFile As String)
newcon.Open "provider=microsoft.ace.oledb.12.0;Data source= " & sDatabaseFile
End Sub
Usage:
Sub Whatever
Dim vFileName As String
vFileName = Application.GetOpenFileName("Access database files (*.accdb), *.accdb")
If CStr(vFile) = CStr(False) Then Exit Sub
Mail_workbook_Outlook_2 CStr vFileName
End Sub
For further information, please see:
Sub Procedures[
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Passing Arguments to Procedures[
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Calling Sub and Function Procedures[
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Application.GetOpenFilename Method (Excel)[
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Programmatically Selecting Files in Excel for Windows and Excel for the Mac[
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