Here it is people, as promised, MarketPlaceRegionSwitch. What does it do? It allows you to switch MarketPlace to USA, Germany, France, Netherlands, etc. Whatever you want - without mucking with regional settings, soft-resetting, etc. "because I can" :P
I DEMAND you read the entire post before using it, because there are definitely things you should know before using it.
This app actually fools Marketplace into thinking you are from somewhere else. This method is not foolproof, and may be circumvented by Microsoft in the near future. It is not for the faint of heart either.
Because developers have been left in the cold for manually verifying their apps are in the correct markets. Microsoft have dropped the ball a few times with "published" apps seemingly not being published at all, or incorrectly. While I'm sure Microsoft will fix these issues in due time (and indeed provide the functionality this program offers) for now developers need to check this for themselves. So no, this app is not meant for end-users, but for developers. If you still want to use it, that's fine by me, but it's on your own conscience
Keep in mind this is a developer tool, for verification of Marketplace presence. I would strongly advise against using this to download apps from market regions that are not your own, and especially not buying them through this app. In fact it is likely the Marketplace will not allow you to purchase from another country than your CC's billing address in either case.
How to use
Now here come the important bits. When you start the application, you will see two text boxes in front of you. MCC (mobile country code), and Lang (language ID). By default they have settings for the USA entered.
You will want to fill these values with the correct values for the market you want to visit. You should have matching country codes and language ID's, but see the note below about that. In 1.1 I have also added a select box with presets that mostly work.
Now, how to find the values you need to enter here:
Hit go, wait a few seconds, and you should be in the market of your choice.
Please note that unlike the other region switching tricks, this one is supposed to work through your CELLULAR connection specifically! Please make sure you do NOT have USB/ActiveSync or Wi-Fi connected!
Notes about the "preset" selection box
While many of these presets work, I have noticed some strange behavior. Often the 'expected' codes do not work if a region is combined with a language, but that language is not from that region.
Take for example, Luxembourg. The preset uses the correct LangID and MCC for French/Luxembourg, but it usually wont work. If you keep the Lang from French/Luxembourg but use the code for France in the MCC box, it usually will work and you will end up in the Marketplace for Luxembourg, not the one for France. You will have to play with it if you want to test for these less common markets. If you have specific notes about which codes work for which specific Markets, please do post them here.
If you are having trouble connecting to the USA marketplace, try using 311, 312, 313 or 314 instead of 310 in the MCC box.
How it was done
The entire thing is done by runtime patching. Functions used to figure out which locale you are in are patched by the app, returning the value you entered in Lang. Accompanied with that, the IMSI is patched and the MCC part is replaced by the value you entered in MCC. This all is a lot more complicated than it sounds
Obviously the app does it's best to restore original behaviour on exit, though I would still advise soft-resetting when you're done with it.
The UI sucks, deal with it. I spent less than 5 minutes on it. I did spend many hours on the actual functionality, though.
The app should remain running while running Marketplace! It will (should) automatically exit once you exit Marketplace. Be sure to use the menu->exit function, instead of the X (the latter will usually just hide Marketplace, not close it).
The method used to patch may cause issues that will not disappear until you soft-reset, chances are slim but things can go wrong.
29.10.2009 - v1.1
Having to restart Marketplace twice without this app to get back to your "home" market should be fixed
If you are a developer for Marketplace and you make use of this app, it would be much appreciated if you would DONATE to me for my time (the link to donate is at the bottom of my signature)
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