Ed Andersen

Software Developer and Architect in Japan

Using a Nokia Lumia 800 Windows Phone on Softbank Japan

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The only official  Windows Phone in Japan is au’s Toshiba IS12T. Not wanting to change plan, I picked up a SIM unlocked Nokia Lumia 800 and put the Softbank micro SIM card from my iPhone 4 inside. If you want a more general guide to setting up Windows Phone for previous iPhone users and what apps should be installed, read Scott Hanselman’s post. Remember to disable iMessage if you are moving from an iPhone.


About the Nokia Network Setup application

DO NOT use the Nokia Network Setup application as it will not make your phone work with Softbank in any way. It tries to set up WAP-era metered dialup connection which Windows Phone 7 does not support any more. If this ever worked, it would cause massive phone bills and general misery. Steer clear.

What does and doesn’t work

Calls OK
SMS messaging between carriers OK
SMS messaging to Softbank and other iPhone users OK
MMS via @softbank.ne.jp NG
MMS via @i.softbank.jp OK
Data OK
Visual Voicemail NG

Setting up data

The Softbank iPhone unlimited data plan works with other phones if you put the “secret” access point details in. The access point name is “smile.world”, username is “dna1trop” – you will need to Google for the password. Insert this access point information under Settings > Mobile Network > Edit APN and you will have data working, including HDSPA which will show up with an “H” icon in the status bar.


Messaging – dealing with the lack of MMS

MMS is supported by Softbank, but only on phone models they sell. Windows Phone 7 has MMS support but because the User Agent is unrecognized by Softbank, they block it at their MMS proxy server. Android users can easily change their MMS User Agent to match a phone that Softbank sell, but the Lumia 800 cannot do this as there is no Interop “root” access available yet. Nokia almost allowed the setting of MMS User Agent in the built-in Diagnostics application but for some unfathomable reason locked the “MMSPage.xaml” screen out – .NET Reflector even shows the registry key that the application would have edited:


Hopefully Nokia releases an updated version of the Diagnostics application where we can set the MMS UserAgent or an Interop unlock for the Lumia 800 is found.

Last year Japan’s networks turned on SMS, meaning you can send text messages between carriers just like the rest of the world. Messages are free between users on your network but about 3 yen to other networks. Japanese text is supported and Windows Phone will even show some basic emoticons out of the box. When somebody sends you an MMS to your phone number or keitai email address, you get an SMS reading “Get media content now”. You’ll be able to see who sent the message but won’t be able to read the contents or directly reply. With Windows Live and Facebook chat built into the phone, this is only a slight annoyance – it is in your best interests to wean your contacts off your Softbank-locked @softbank.ne.jp keitai mail address anyway as this will make it painless to change provider in the future once Japan’s carrier market has loosened up a bit.

Somebody tries to send you an MMS and this happens

You can still use the @i.softbank.jp email address that you got with your iPhone as it is a standard IMAP account. Just add it as an extra email in Windows Phone and it will auto-detect the settings. You can email other keitai email users as it counts as a “keitai” email address so will not be immediately blocked by spam filters. When somebody sends an email to this address, you get a “flash” SMS. This system was used on the iPhone before it got MMS support.

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Hi! 👋 I’m a Software Developer, Architect and Consultant living in Japan, building web and cloud apps. Here I write about software development and other things I find interesting. Read more about my background.

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12 responses to “Using a Nokia Lumia 800 Windows Phone on Softbank Japan”

  1. Richard Avatar

    Hi, I know this is totally unrelated but do you have an experiences with unlocked foreign phones in Japan?
    I am coming over to Japan for work and I have nokia n8.
    I was wondering if I could get it work in japan on either docomo or softbank. Any recommendations?

    Thank you

  2. Great info:) Do you know if it also works with a foreign sim for sms?

  3. Anonymouse Avatar

    Hi, Ed.

    Yeah, I got my wife an HTC Radar and am finding that her Softbank silver SIM (originally from an Android) works well except for the MMS settings.

    Looking through xda-developers, so far there is no Interop access for 2nd gen HTC phones, so there’s only so far down into the innards I can go.

    I do have developer access to the device so I can push my own apps, but I believe getting down to the MMS settings is going to require additional privileges.

    One of the other problems I’ve noticed is that sometimes mail subjects (particularly of gmail variety) will lose their Unicode-ness and look like switch to Shift-JIS and become unreadable. I don’t know if this is a bug in how WP7 handles Gmail, a bug in Gmail in general, or something else that maybe WP7 can work around by understanding if mail is a mixture of both Shift-JIS and Unicode. Probably not something fixable at the user level, either way.

  4. Kit Fil Avatar

    I have a regular iphone 3gs unlocked and jailbroken with tmobile. Does anyone know if i can upgrade it with no problem to 4.2 cuz I knw wen i barely got my iphone i cldnt upgrade it other wise it wldnt work.?

  5. Hi,

    Any idea if the new Lumia 1020 will be working or be available in Japan? I’m with KDDI on IPhone 5.. Want to make the switch.

    Thank you!

  6. steveirvin Avatar

    Japan is not what it used to be. Technology is too tied up in politics and manufacturer’s rights or restrictions with other providers and makers. this world is a mess. i went to three telcom stores in Japan today. No SIM cards for sale. this is ridiculous. Just when AT&T gets nice enough to offer unlock codes, you have no need for that if you can’t get a local SIM in a foreign country. The FB twitter skype magicjack Viber etc world is only gonna get bigger. Cell phone companies suck but hey, the time of coming to Japan to get a camera cheaper was long gone decades ago. the food is still good.

  7. Hey,

    I know this msg is pretty old, but what about the new NOKIA models? Does a 920 or 925 work with iphone 4 SIM cards from Softbank?

    If you’re still around thank you for the answer.

    1. I see no reason why they shouldn’t work for calls, SMS and data if they are unlocked. You’ll need the “smile” APN settings. MMS won’t work.

  8. @George, how was it? Did you successfully use your iphone4 sim to your lumia 920/925? I’m planning to get a 925 and use my iphone4s softbank sim. Also, how’s the phone bill? Did the unlimited packets works? Sorry for the massive questions. Thanks!

  9. Nagoyablue Avatar

    Hi, I just inserted an iphone 4s black sim into my 920.

    Phone works fine, just wondering if anyone got charged for the data, or if the capped fee works on a non-softbank non-iphone?

  10. Hi, I did the same with a Lumina 920. Works great, except when I try to use 3G, then the phone gets really hot, and the battery drains at about 30% per hour! Did you have any problems like this?

    Or maybe I’ll try a different firmware.

  11. 義侠心がたいへん強く、社会への柔軟性に富む。

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