osu! logo shows up, but game not launching

If the osu! logo is showing up, but the game's not launching afterwards, there might be a few cases:

If logs are showing this line:

mscoree:expect_no_runtimes Process exited with a Mono runtime loaded.

..then the issue is dotnet being misconfigured in your prefix.

Fix should be as simple as: osu-wine --fixprefix

If Wine is arguing about a random error (usually starting by c0000..) it probably means you don't have read/write permissions in the game's folder.

That usually happens when playing from a custom drive, I recommend following this to mount your external drives properly: https://github.com/ValveSoftware/Proton/wiki/Using-a-NTFS-disk-with-Linux-and-Windows

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