Update onboard-downlevel.md

Link fix per build report

Author: chrisda

defender-endpoint/onboard-downlevel.md

@@ -180,7 +180,7 @@ Follow the steps in [Run a detection test on a newly onboarded device](run-detec
 1. Download the following and place them in the MMA folder:
 
     - Update for customer experience and diagnostic telemetry:
-      - [For Windows Server 2008 R2 x64](https://www.microsoft.com/download/details.aspx?familyid=1bd1d18d-4631-4d8e-a897-327925765f71)
+      - [For Windows Server 2008 R2 x64](https://www.microsoft.com/download/details.aspx?id=48641)
 
     For Windows Server 2008 R2 SP1, following updates are also required: