Hello fellow people! I have quite an devasted problem, that I really need assistance with, these few hours I have been trying to get my phone to work. But apparently no luck, and I come here for your help! (I've searched everywhere, trying to find every possible solutions, such as drivers, switching computers, ports, etc etc)
Anyway, let me explain to you what's wrong:
Model: Sony Xperia Z3 Compact(D5803)
So apparently, my sister had forgotten her passcode. Don't ask me how(She has protection on, so it's fine when the step comes to put in her Google account details). Right, so I went ahead and used PC Companion: Well, so I went over the usual stuff, and clicked on "Repair my phone/update". Went ahead to the step where it required me to: First press volume down, then insert the USB cable. I did, BUT it didn't even recongize it, PC didn't even react and the phone just went to charging mode.
So I attempted this about 30 times, but it kept on going on charging mode. I myself have a Z3, and decided to have go on it. So I tried it with mine, and in the first attempt, it found the device and displayed it as "S1 flash device" and my Sony Xperia Z3 was a success, but not my sisters!
So I got really frustrated and searched the net, googled, which handed me into few more solutions:
1) Device manager, I did check it
2) Changing ports - Tried it. / Usb 3.0, 2.0, different pcs
3) Changing to different PCs (OS: Vista, 7, 8): 3 different PCs, not one reacted the Z3 compact would just charge.
4) Installing custom drivers, from few solutions that said: Install all S1 drivers, I did that too.
5) Windows Media Player drivers, and Sony solutions, tried it aswell..
6) Inserted a SD card, yup tried it.
7) Tried it with 6 different USB cables
😎 Reinstalled PC companion, used USBDeview, didn't even detect anything (Remember on: 3 computers)
9) Performed a soft reset either way(Power button + volume up) - Three vibrations (or used a pen and pressed on the little button on the side of the phone) - Soft reset did not work either.
10) Booted up the phone, even from the passcode screen the PC wouldn't detect it. It would charge, but no sign of detection.
11) Java installation
And few more solutions..
Hopefully you lads can help me out here! 
TL:DR; Whenever I try to get my sisters phone into flash/usb/ mode, by pressing volume down then inserting the usb cable. The PC wouldn't detect anything, even not device manager and the phone will go ahead to charging mode. But, when I tried it on my own Xperia Z3, it worked on first attempt.
Regards,
C Hay
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