My sony ericsson mw600 is frozen and i cannot reset it.

Below solution from talk.sonymobile is perfectly worked for me. Please try this:

i got the same issue and i have to fix it myself. Here is the step:
1. Under the female micro usb has a "small black plastic film" was glued to cover a "s c r e w". pull this film out.
2. "S c r e w" out this "s c r e w", pull out the bottom cover of the WM600. note: keep your eyes on the plastic power button, dont get it lost.
3. Look care fully inside u will see the battery, there is a small gap between the battery and it cover, use tool like tweezers to separate the battery and it cover a little bit. after that the WM600 will turn off.
4. tied everything back to its original
5. charge it for a while and then press power button to turn it on.
if you got any problem of my ideas, leave a comment, i will attach the pictures for each step.
Sorry for my bad english.
Good luck.

If there reset function does not work then there is a serious fault in the memory or there is a damaged board . It is possible that in such cases there willnot be any communication and can be a serious fault on the board.
So If you are not able to detect the headset player on your Phone or that the bluetooth does not come active at all then the unit is damaged and you must take consensus with the service center.
There is not much to be done if the board is faulty but it is worth to take an opinion before you further damage the device , in case the unit can be opened and the main board restored after a full reset fom within or if there was a case of moisture build up within that had caused this fault.
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