Released on May 15. Diablo 3 is the sequel from Diablo 1 and 2 and Blizzard newest game. Here is a list of the different Diablo 3 error you can run into. The list might be missing some and is not complete. Most of the errors you’ll encounter is at the authentication and therefore the infamous error 37, the login server is busy.
Take a look at the known issues list on battle.net
Updated: It seems the Asia server isn’t that crowded so if you just can’t live without playing and don’t care which character you play, you can start a hero on the Asian server.
Error 12. “This Battle.net account does not have a Diablo III license attached to it. (Error 12)”
If you're experiencing Error 12 when attempting to log in, please let us know in this thread and provide the following information: Are you attempting to log in to a region that is not your home region? (see Global Play FAQ for details) If yes, do you still receive an Error 12 message even when logging into your home region? What is your home region/where are you logging in from?
Error 33: “(Error 33)”
If you're receiving an Error 33 message when attempting to log into Diablo III, don't panic! This is because Diablo III is not yet live in North America. As a reminder, Diablo III will launch on May 15 at 12:01 a.m. PDT (Pacific Daylight Time). Until that time, you will be unable to log in.
Error 37. “The servers are busy at this time. Please try again later. (Error 37)
If you just have to play, try out the Asian server.
"It is possible to get ERROR 37 (The servers are busy, please try again) when logging in if the servers are under heavy stress. This error literally means that the servers are busy and that you should try again, so please try again in a minute or so!"
Error 75: “There is a temporary outage of the Battle.net service. Please try again later. (Error 75)”
Blizzard info: Most likely because of Maintenance and update
Error 108: “Error 108 occurred. It’s unable to open installer tome2.mpqe (Error 108)”
Yes, the 108 error is likely caused by partial or incomplete files. You should be able to launch the downloader again, point to the directory holding the "Diablo-III-8370-enUS-Installer" to verify game files and correct any missing data. Let the downloader sit there, even though it's at 100%, and it should eventually auto-launch the installer. Alternatively you can download the client again (and make sure you don't close it prematurely this time), or wait for the new installer that includes streaming and doesn't require a full download.
Error 3003: “Unable to connect to the service or the connection was interrupted. (Error 3003)”
Error 3006: “The request has timed out. (Error 3006)”
Error 300008 “The request timed out. Please try again. (Error 300008)
Error 315300: “Your login information was incorrect. Please try again. (Error 315300)
Error 317002: “Unknown (Error 317002)”
We're currently performing urgent maintenance in North America to resolve a variety of issues affecting the game. As a result of this maintenance, though, we anticipate that players will experience some interruption in communication, ability to log in, use of in-game features (like creating or joining games), and disconnections. This error may be a direct symptom of the ongoing maintenance. We definitely appreciate the reports and will be providing updates here:http://us.battle.net/d3/en/forum/topic/5051765603