Share your experience!
I am currently experiencing a problem with my Sony M5 dual. When I power off my phone to remove my simcard then power it on, the homescreen appears for 2-3 seconds then restarts again from the black screen "SOnY xperia". Then restarts all over again.
please help
Hi @Hushberry, sorry to hear about this. 
Is there any change if you insert the SIM card in your device and then power it on again, or do you end up in the same restart loop? If you have a SD card mounted in the device, try removing it from the device and then power it on again.
You can also press and hold the volume up and power button at the same time for 10 seconds and then start the device again.
If you still can't get past the initial start up screen, try performing a software repair using Xperia Companion. Do note that this will delete all data stored on the internal storage of the device.
Let me know how it goes! 