1. Install 10.2.1 License Manager, if the License Adminstrator shows click "Start/Stop License Service" and click "Stop" and close it.
2. Copy ARCGIS.EXE and services.txt to "C:\Program Files (x86)\ArcGIS\License10.2\bin" and overwrite.
3. Open LSAdmin, click "Start/Stop License Service" and click "Start" then "Re-read Licenses".
4. Open Start Menu-Programs-ArcGIS-ArcGIS Administrator .
5. Inside the "Desktop" folder, select "Advanced (ArcInfo) Concurrent Use".
6. Click "Change" under the "License Manager" and type in localhost (or whatever port you put in the services.txt file).
