Share your experience!
Hey,
I have a problem... I can't update my Sony Z3 Tablet to Android Lollipop... This is really nervy! I contacted the support twice and I got twice a message back that I should wait... So 4 monthes later... NOTHING!... OKAY. I really want to update to Android L... I think I got an prototype but I don't know... I can't see the IMEI only the IDID and the serial number... This is strange... I have the WIFI edition with 32 GB... modell number --> SGP612
I hope that someone has a solution for this problem... 
kind regards,
Lorenz
WiFi only devices doesn't have a IMEI number, they have IDID numbers instead. Send me a PM with your IDID number and I can check for you if the device is a prototype.
If the device is a prototype you might not get the update as these devices are not intended for end users and doesn't work the same way as retail units.
I have the exact same issue, my Z3 does not report the update, even on PC companion.
I have PURCHASED this tablet on JAPAN, but I live in BRAZIL. I have read this might be the reason, that the tablet will only update if I am in JAPAN? That is probably wrong ... I hope.
IDID:
Serial Number: CB5A23J03F
Model SGP612
Android 4.4.4
Kernel 3.4.0-perf-gd4d661a
BuildUser@BuildHost #1
Fri Sep 19 18:10:07 2014
Build Number
23.0.1.A.0.167
Software ID SGP612 R6B
Well, ok, I found out that the Japanese "thing" was a thing indeed ... only version still stuck with 4.4.4, that is very weird =x
Flashbooted to US, 5.0.2 working fine. I will never get it why specific regions can't get the update despite it working on their region (I can switch to japanese on 5.0.2 xD)
Thanks to Alexdon for making me aware that IDID's are not meant to be public 
I also have a Japanese tablet that won't update to Lolipop. Same thing as above PC Companion says it's up to date as does the update center on the tablet.
So how can I update it to Lolipop?
You have to do it manually using flashboot, which is not really easy for layman to do. If you make any mistakes, you might brick your phone (ok, you won't, flashbooting again with the correct firmware would fix it, but if you can't do it right the first time, might have problem on any number of times).
Also, note that this usually voids the warranty (in this case, since you are flashbooting without rooting and using an official Sony release, I THINK it doesn't, better wait for a support member to pitch in.
I don't know if it is ok to link to tutorials to flashboot here >.> anyway I did it with mine and it works wonders. But just so you know, there is little benefit to upgrading to lollipop other than some fancy visuals. No real new feature (new features are promissed mostly on Android M, the next version) other than some tweaks to notifications and the fact Sony opted to remove their personalized top bar in favour of the new Lollipop one, which is very similar to Sony's
Thanks for replying! Was begining to think I was being ignored.
I want Lolipop as it allows you to once again move files and programs to the extention sd card. Something Google decided to take away with KitKat.
I support doesn't reply I'll PM you for the link, if that's okay?
Wow! More than 24 Hours and still nothing from support!!!!
I thought these forums were for us to speak to Sony and recieve help with specific problems. Looks like Sony's support staff have the day off or can't be bothered to check the forums. Guess they're too busy playing with their PS4s or trying out the Xperia Z4. 
Well this is not a chat, it should take 2~3 business day for an official response.
Anyway, you CAN move files to any extension SD or USB drive on KitKat, just the same as with Lolipop. I did that on 4.4.4 with easy, the caveat is: it must be with one of the file navigation tools that comes bundled with the device, any other app will get a "not allowed" message (that in Lolipop too).
For most (all?) Sony devices, the app that will allow you to do that is File Commander. Not the best app for that but does the job.
Reading FROM SD/UDB can be done by any app.
Thanks Caiobrz! You've been very helpful on all counts.
Shame I can't say the same of the so called "support team".