I know, I better should be posting in the XDA-Dev forums, but I'm more of a Neowin fan that....even if I might not get the support for my device here.
I've got a Sony Xperia Z (C6603) a while ago, actually 1.5 years ago. It's a SL version from T-mobile. Recently I upgraded my phones from 4.3 to 4.4.2 (via Sony's push update). Sony reportedly sad this update is buggy due to the Google Play Service draining all the battery. Nevertheless, I did because I notices a strange other bug, affecting my Android OS, soaking my 3G network traffic. In 2 week, it's produced about 1.5GB of traffic. Prev month also almost as high, but not nearly with 850MB. So I upgraded, after the upgrade, the phone was essentially useless. Low battery, only possible to charge while turned off. App laggy. Apps crashing. Useless piece of plastic really, far from a "smartphone". So lets trash Sony and everything, let's go all in backdoor on them and go for "root", open bootloader and install the stable Cyanogen mod's Yuga on this.
1. First, I tried to root the device, with little luck. Used dooms rootkit (v17) as they tutored my on XDA. After reboot, I still wasn't root. [FAIL]
2. Let's see if I can open the bootloader maybe. On the sony website they asked to check in the phone services if it's even possible to "open". Did do that but it sad, "not possible". Most likely, coz my bootloader wasn't the factory version, it's TELEKOM-something-something. But I anyway aquired the unlock code from Sony. [FAIL]
3. Tried not to factory reset via options. [FAIL]
4. Now comes the hard factory reset, done with the PC Companion. This worked on the 2nd go. Phone got wiped and clean Android 4.4.2 launched. It's got more snappy then prev, but other then that. Still no root. Bootloader still locked. [YEEEY]
5. _______________________________is there any possible solution to get root or open bootloader? Does T-mobile do this after they give you no more software support?
Thanks in advance for the opinions and suggestions.