Hi have been stuggling to find the right software to unlock my phone with cid53. This is what i ended up doing, i sent a email to vodafone uk with my iemi number asking for my NUC code not telling them its a payg phone as im on contract. They got back to me and asked for my security 4 digit pin so i rang them up (191) and explained to the guy what the email had said and gave him my 4 digit security code. I then told him my imei no and he emailed me the code with no problems and its know unlocked:D He did not notice it was a paygo phone as i have only bought it new about 2 weeks ago this should of cost me £20 for them to unlock it. its worth a try before you brick your phone I guess you can do this with any voda phone not just k800i:rolleyes: