For those, who have issue with config

[Kenny690]

So, every time I've tried to start configuration instead of game - I had nothing. Problem was:

Cannot mix incompatible Qt library (version 0x40806) with this library (version 0x40801)
Aborted (core dumped)

What have I done...
Open the terminal, write:

$ locate libQtCore

then, you should have something like that:

/usr/lib/i386-linux-gnu/libQtCore.so.4
/usr/lib/i386-linux-gnu/libQtCore.so.4.8
/usr/lib/i386-linux-gnu/libQtCore.so.4.8.6

All you need is libQtCore.so.4 and libQtGui.so.4 (they are in same folder).
Run this command:

$ rm "$HOME/.steam/SteamApps/common/MountBlade Warband/libQtCore.so.4" && rm "$HOME/.steam/SteamApps/common/MountBlade Warband/libQtGui.so.4" && cp /usr/lib/i386-linux-gnu/libQtCore.so.4 "$HOME/.steam/SteamApps/common/MountBlade Warband" && cp /usr/lib/i386-linux-gnu/libQtGui.so.4 "$HOME/.steam/SteamApps/common/MountBlade Warband"

After that, everything should be working. :)
(Sorry for my English. I'm russian.)

(To dev's. Can you make some kind of detection of this libs and use them instead of yours? Thanks in advance for answer)

[Mortal Wombat]

Thank you very much. Your solution worked for me.

[Kenny690]

You are welcome. :)

[Antonio Huertes]

Originally posted by pootatosalad:

Thank you very much. Your solution worked for me.

¡¡For me too!!!
Thanks!!!

[alexshots]

inspired on ubuntu 14.04 LTS 64bit！

[Cyrhinka]

Thanks,

I installed the game this week and I had the same error..

It worked for me on Ubuntu 16.04.

While I had

$ locate libQtCore
/usr/lib/i386-linux-gnu/libQtCore.so.4
/usr/lib/i386-linux-gnu/libQtCore.so.4.8
/usr/lib/i386-linux-gnu/libQtCore.so.4.8.7
/usr/lib/x86_64-linux-gnu/libQtCore.so.4
/usr/lib/x86_64-linux-gnu/libQtCore.so.4.8
/usr/lib/x86_64-linux-gnu/libQtCore.so.4.8.7


I copied i386 versions and it let me open the config window.

[Ocean]

I just deleted both libqtcore files and it fixed for me