I have been using the following command to open another MDB Access file via VBA:
Shell \"cmd /c \" & Chr(34) & strNewFullPath & Chr(34), vbHide
I use this function when working in Access 2003:
Public Function RunExternalMDB(MDBName As String, WG As String, UsrNm As String, Pwd As String)
Shell "MsAccess.exe " & """" & MDBName & """" & " /wrkgrp " & """" & WG & """" & " /user " & UsrNm & " /pwd " & Pwd
End Function
This does work in Runtime mode : )