Not tested, but you could try this

[vba]

Dim wb As Workbook, myFileName As String, myVal As Long, myMax As Long
Dim strPath2 As String, fname As String, i As Integer

If MsgBox("Have you printed your worksheets yet?", vbYesNo) = vbNo Then Exit Sub
Application.ScreenUpdating = False
'Sheets("ESTIMATING").Select
'ActiveWorkbook.Save
On Error Resume Next
strPath2 = Dir("\\5.111.222.646\Estimating\", vbDirectory)
On Error GoTo 0
If strPath2 = "" Then


MsgBox "make sure your network connection is turned on then try again"
Exit Sub
End If

fname = Dir(strPath2 & Range("B11") & "*.xls")
If fname = "" Then
myFileName = Range("b11").Value & "1.xls"
Else
Do While fname <> ""
myVal = Val(Replace(Replace(fname, ".xls", ""), Range("b11").Value, ""))
myMax = WorksheetFunction.Max(myMax, myVal)
fname = Dir()
Loop
myFileName = Range("b11").Value & myMax + 1 & ".xls"
End If
ThisWorkbook.SaveCopyAs strPath2 & Application.PathSeparator & myFileName
[/vba]