Ok Here is what i have so far:

Sub SaveAsCell()
Dim strName As String

On Error GoTo InvalidName
strName = Sheet1.Range("B26")
ActiveWorkbook.SaveAs strName

Exit Sub
InvalidName: MsgBox "No LS or G Enter " & strName & _
" Please Enter Number", vbCritical, ""
End Sub

Now I am not sure what to add. I want it to go to E26 on error of B26 (if its blank basically i want it to look in the other cell). I am lost at what to do