It recently came to our attention that it is possible to install these games on top of World of Warcraft version 4.0 and it'll revert part of the data files to 3.x or 2.x, corrupting the game in the process. Please don't install the old games if you've applied the 4.0 patch. After applying the 4.0 patch, you should have all of the files you need so if you bought a new game, just upgrade your account on Account Management and then log onto your existing game client.

Two things can happen if you try installing the old game on top of 4.0:

You'll get an installation error when the installer can't find the old game file it needs. This tends to happen on older installers.

After installing Burning Crusade or Wrath and the little tools patch, you'll be greeted by the error "Launcher requires write permission to the World of Warcraft Registry key to successfully locate and run the game"
http://img258.imageshack.us/img258/300/launcherrequireswritepe.png

If you did end up installing an old game on top of 4.0, please just delete the entire game folder and reinstall using https://us.battle.net/account/downloads/WoW-4.0.0-WOW-enUS-Installer.exe

Please only post if you have concerns about installing old game versions on top of new one, not miscellaneous install issues that have nothing to do with this post.

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Q u o t e:


I know most of them don't, but I think it's just because a lot of people see a blue poster and they want to jump at the chance to get an answer; I saw it and was about to ask, when I noticed this post above. ^

Admittedly, I did the above and it worked fine for me? It didn't corrupt my installation... is there something wrong with my WoW then?

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Some of the people are getting odd error messages regarding common-2.MPQ when applying the 4.0.0 migration patch since the 4.0.0 and 4.0.1 data were already there. There's a weird us.version.worldofwarcraft.com error right now that prevents me from patching my 3.0.1 client, getting me stuck at the launcher and the -1% screen. We're looking into that issue right now. If you can get it to patch back to 4.0.1 without errors, more power to you. :)

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Q u o t e:
so I bought and attempted to install WotLK today. Now I can't play. Is there anyway to get it back to 4.01 without completely uninstalling the game and reinstalling everything? That would take me a week of downloading at least. I have slow internet.

Thanks for any help on this situation

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nvm. It broke.

The launcher seems to be stuck and be in a confused state of panic (stuck at 0.0/X.X GB) if you tried installing 4.0 over a bad old revert. It seems to be best if you uninstalled the game completely and install using https://us.battle.net/account/downloads/WoW-4.0.0-WOW-enUS-Installer.exe

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Q u o t e:
Well I have the same problem. I click on the launcher and it brings me to the "Launcher requires write permission for WoW" and i have no idea what to do. I have been ready all the forums and nothing helps. Running administrator does'nt work either. I have no idea what to do! Please help me, I wanna play!

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You installed the old game on the new one. Please delete the game folder and install ONLY the new client. The old Launcher doesn't know what to do with the new game files so it gets stuck on that error.

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Q u o t e:
Datth the Mac Technical Support needs this Topic!!

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Unfortunately I don't have a Mac handy to see what type of errors will come from installing the old game on top of the patched game.

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Q u o t e:


I helped a guy upgrade his account.
can we have a box comes up when the player hits the cap for the expansions

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We tend to avoid advertising the expansion packs and other stuff in-game like that. I think you not gaining any experience points should be a good indicator that you're stuck on an account level :)