Is this a wireless receiver? Or hardwired? If hardwired on coax or Ethernet?
Do you have a link light on receiver?
Client error means cannot find RG (residential gateway) to register (activate) receiver. If just placed at a TV and plugged into coax wall plate, does not mean that connection is part of network at splitter. Best is to place unit at known working TV receiver, depress OK when retry screen displayed, and depress OK again when update screen appears...allow about 5 minutes.
Once verified working at good location move to desired location...if does not work, wiring issue, requesting a service tech on inside wiring issue is billable service call...minimum $99.
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