Nokia 5300 stuck in Test Mode

Last Saturday I bought my daughter a brand new Nokia 5300.

I set the phone up for her and everything seemed to work just fine.

Then late Sunday evening she brought the phone to me saying it wouldn't
work. I looked at the screen, and it said 'Test Mode'. None of the buttons
had any effect, and neither did switching the phone on and off. The phone
seemed totally dead, with just the legend 'Test Mode' on the screen.

In the end, I took the back cover off and removed the battery, waited 10
seconds and re-fitted it. The phone now seems to work fine again.

Has anyone any idea what caused the phone to go into 'Test Mode'? Is this
problem anything to worry about? The shop has offered to replace the phone.
--
Mike
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reply-

I wrote:
>
> Last Saturday I bought my daughter a brand new Nokia 5300.
>
> I set the phone up for her and everything seemed to work just fine.
>
> Then late Sunday evening she brought the phone to me saying it wouldn't
> work. I looked at the screen, and it said 'Test Mode'. None of the
> buttons had any effect, and neither did switching the phone on and off.
> The phone seemed totally dead, with just the legend 'Test Mode' on the
> screen.
>
> In the end, I took the back cover off and removed the battery, waited 10
> seconds and re-fitted it. The phone now seems to work fine again.
>
> Has anyone any idea what caused the phone to go into 'Test Mode'? Is this
> problem anything to worry about? The shop has offered to replace the
> phone.

Additional information:

Apparently my daughter saw that the battery was low, so she switched the
phone off and plugged the charger lead into the phone socket.

Then she switched the charger on at the wall socket, and it was at this
point that the phone went into 'Test Mode'.
--
Mike
-Please remove 'safetycatch' from email address before firing off your
reply-