If you are still having issues launching the client, the following procedure covers how to properly set up your environment to address a comprehensive set of possible issues. It's the best starting point since your error message could be caused by any number of things.
For those users having difficulty logging in to the Beta it appears that the issue can be caused by a combination of factors. The following is a list of ways to set your game up so it is running from a clean slate. Please perform ALL of these tasks BEFORE launching the game client, as attempting to launch the game with this list only partially complete may undo your efforts.
1. Delete/uninstall the Arcade Beta, if you have it.
2. Delete/uninstall any current Installed version of the HotS Multi Beta.
3. Delete your Battle.net and Blizzard Entertainment folders found in the following locations:
• Win7: C:\ProgramData\
• XP: C:\Documents and Settings\All Users\Application Data\
• Vista: C:\ProgramData\Blizzard Entertainment\
• Mac: Users/Shared/
4. Delete your Variables.txt found in the following locations:
• Vista/W7: C:\Users\<username>\Documents\StarCraft II
• XP: C:\Documents and Settings\<username>\My Documents\StarCraft II
• Mac: Documents/Blizzard
5. Reset your router.
6. Restart your computer.
7. Run the Installer, with no other programs running in the background.
8. After fully installing, make certain you run the game from the executable in the root directory.
• PC: C:\Program Files (x86)\StarCraft II 2012 Beta\
• Mac: Applications/StarCraft II 2012 Beta/
• Do not launch from the Switcher. This will not update your client version to match the version on the server.
• Do not launch using third–party software such as Steam.
9. If, when you log in, you have two possible character accounts, try them both. If neither works, post in this thread to have Customer Support review your account in case it is not flagged for proper beta access.
If, after all this, you are still having issues, post a new comment on this thread. Please include your DxDiag, what behavior you observed during the install (was it slow, did the bar jump from 1% to fully installed, did your computer get struck by lightning, etc?), and where exactly in the process you’re getting hung up.
Every detailed report we get makes the game that much more stable and will lead to a smoother and more awesome launch of the full game. I assure you we do read every thread and your feedback has been phenomenal in helping us make the game that much better.
Please create a new thread if you try these and still have difficulty loading in.