I hope someone can get me to finally debrand my phone. I have it on a Vodafone contract and have held back from updating the firmware that vodafone have released as I have read that once I do that I will never be able to debrand it after that (is that correct?)

I have read many threads and web pages on this. I have set up a goldcard and I have downloaded a few programs to put the generic HTC firmware on the phone. I keep getting "error 140" and "error 171" problems and the process keeps stalling.

Surely I can't be so unlucky to not have the only phone that cannot be debranded. I must be going wrong somewhere. I would be grateful if someone can give me foolproof instructions bearing in mind the error codes I have included that will get my phone sorted out.