[Galaxy Note II Q&A, Help & Troubleshooting] Irish Steve:
Standard device, running 4.4.2, not rooted or changed other than by downloads provided by KIES, originally on 3 Ireland network, was unlocked and moved to Vodafone over 12 months ago with no issue, using unlock code provided by 3 after the end of contract period was reached.

Had a few strange issues recently but nothing I could be sure of, then one night this week, the phone locked and would not accept any key presses. Removed battery to force power down, then restarted, which has always worked in the past on the rare occasions when this has happened, but this time, when it restarted, it asked for a Sim Network Unlock PIN, which at the time I didn't recognise as being the unlock code supplied by 3.

I don't know if there are issues about the number of times this code can be entered, if there are, due to all sort of errors by Vodafone Support, that limit has probably been exceeded.

The other possibility is that a hardware issue has developed, but as it is only the phone network won't work, my instinct is telling me that this is a software and security issue that may have been triggered by too many failed unlock requests, though it still asks for an unlock code on power up.

So, what have I tried. After several frustrating calls with Vodafone and Samsung support failed to resolve the issue, I dismissed the PIN request and made sure I had some backups of things like Contacts, which worked, so the phone can communicate via USB, and it's also working with no issues via WiFi networking, as I can access things like Facebook via WiFi. My Google account is also working, it's downloaded and updated the applications that are installed on the phone,

In the absence of any real assistance from Vodafone or Samsung, in desperation, I've tried a factory reset, and also tried wiping the cache, but neither of these options are getting rid of the Unlock Sim request, which suggests to me that there is a flag or code somewhere deep in the system that's not allowing a full reset, and that may be related to too many failed Network PIN Entries.

Can I recover this phone, or am I better to just abandon it and get a replacement device, which in all honesty I don't need, the Note II is doing all I need at the moment, and a replacement is going to be an expense I'd rather not have to commit to right now.

I have all the details of the versions, IMEI etc, they are all accessible from within the phone using various *# codes, and they all are still correct and match what they should.

Talking to a local repair shop, if they ask for an unlock code, they are saying that the code they get will be the same as the one I already have received from 3, and as that seems to be not working, they are saying there's no point getting a code from them.

So, where do I go from here? Somehow, I think I need to find a way to wipe everything in the phone, and then reset the IMEI to the correct value, which should in theory allow the device to work again, and recognise the unlock code. That's a lot more than I've done on a phone, I'm computer literate, but not Android and phone experienced, so a lot of the buzz words are not familiar, or mean different things to what I've been used to on other systems.

If I am going to be completely wiping it all, is there any way I can change the service provider to get rid of the issues with the network unlock code, or is that asking for more aggravations?

Thanks in anticipation.