Sub changeLinks()

Dim ohl As Hyperlink
Dim osld As Slide
Const serverold As String = "http://www.technologytrish.co.uk"
Const servernew As String = "http://www.whatever.com"
For Each osld In ActivePresentation.Slides
For Each ohl In osld.Hyperlinks
If ohl.Address Like serverold & "*" & ".pdf" Then
ohl.Address = Replace(ohl.Address, serverold, servernew)
End If
Next ohl
Next osld
End Sub