You should be able to update the M1XEP from 2.0.48 to 2.0.51 in one step:
- Under the Enroll/Update Control and Devices Window highlight the M1XEP
- Click Update
- From the Update Window in the Application Dropdown select 2.0.51
- Click Update
- Once the Update is complete you will need to wait approximately 10 minutes before attempting to reconnect with ElkRP2