M2 unable to screen mirror. Error message 'your output device does not suport HDCP cannot mirror'

[Claire8]

Hi, I have the same make and model as my partner (Xperia m2 D2303).  His can mirror to our TV through our M8 android box. But mine comes up with the message : 'mirroring error. Your output device does not support HDCP.  Cannot mirror. You can still mirror some apps and unprotected content to this device. ' how can this be fixed? preferably without rooting the phone. many thanks 

[MarlonUk1]

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