Error 37. Error 3003. Error... well, you get the idea. Diablo III's less than helpful approach to troubleshooting has seen Blizzard cop a fair bit of flak since the game's release. Now, in the last 24 hours, Error 82 has made an appearance, confounding many international users who are no longer able to use their keys to play the game in their language of choice... which isn't necessarily their native one.
As outlined by user "RodrigoMF" in this 39-page thread of disgruntled gamers from Spain, Russia and Portugal, among other countries, those who purchased a key for Diablo III in their native language have suddenly found themselves unable to use it:
It seems that as of today (Jun 8th, 2012), Battle.net is imposing regional language restrictions, forcing players to play Diablo 3 in their "native client language".
Upon login, players running Diablo 3 on a language different from their region are being prompted with Errors 81, 82 or 84. All of them read as follows: "The client does not match the accounts native language. Please, use the game native client".
Blizzard responded to the backlash with the following post:
If you are experiencing an error 81, 82, 83 or 84 when trying to log in to the game, it's possible that you are attempting to log in using a language that you are not authorized to use. The Russian, Spanish, and Portuguese versions of Diablo III are among some of the versions that can be language-limited.
Your game language and interface will remain the same when you change regions. If you purchased the full-language version of Diablo III, you will be able to play in all available languages in all regions. To play in a different language, you will first need to download the Diablo III game client for that language from Battle.net.
Essentially, language limited keys can only be used with game clients of that language. Previously, a player could use their key with any game client.
From what I can gather, the issue is that international players who want to play the game in English, say, because they're unsatisfied with the translations in their native version, no longer have this option, despite it being available hours before. It's important to note the change does not stop players from connecting to servers in other regions, as outlined in the game's Global Play FAQ.
I guessing Blizzard made the change to combat the sale of discount Russian-language keys online, though it's odd it made the change now, rather than before release. StarCraft II already imposes this restriction, so it's hard for the developer to use the technology excuse.
It's unlikely to affect local players -- unless you happened to purchase such a key -- but let us know if you've seen the error.
[Thanks Cameron for the tip!]