Unlocking a Vodaphone mobile

Posted by dougproctor
Bought a Vodaphone locked phone a week or so ago. My buyer asked and got an unlocking code today from Vodaphone but I have imput this six times and it keeps coming up with "Invalid Sim Lock".
Vodaphone have assured him it is the correct code but it won't work. I started the phone with a non Vodaphone sim card in and it comes up with the input unlock code message. Put it in and get the message above.
Is there any way of doing this please? Anything else I can do. The only thing I have done is to upgrade the operating systyem from WM5 to WM6.
Thanks
Doug

Posted by arien617
doesn't SIM lock mean PIN code?

Posted by dougproctor
Don't know. Anyone?

Posted by totalgsm
Which phone?

Posted by dougproctor
Treo 750V.

Posted by dougproctor
Done it on the 8th try!!
Doug