World of Warcraft Retail/Classic - Game initialization failed: U / Game initialization failed: I

[jhinzuo]

Seems like a couple of Blizzard games have one thing in common which is this error.

World of Warcraft from Vanilla (1.X) all the way to Warlords of Draenor (6.X) worked fine without issues on BOX64 with the exception to vanilla needing BOX64_SAFEFLAGS=2.

When I tried running anything newer than the mentioned expansions, it fails with either Game initialization failed: U or Game initialization failed: I.

World of Warcraft:Retail (current expansion) is affected ( this version is also free2play until level20 for testing)
World of Warcraft:Classic ( all flavours) are affected aswell.
**Private-Servers using versions 7.X up to current are also all affected.

Both versions run fine under Wine without BOX64 and dont need the Battle.net launcher to play these games aswell so i think the culprit might be BOX64.

I attached a log but the game doesnt seem to print anything wrong so i added +seh in my log.

wow_2025-10-12_14-38-45.txt