root needed to launch X11 application

I'm building a Qt application using QML technologie. QML use OpenGL. The computer running the build is a CentOS 6.7, with intel GPU. I'm using it only on SSH, and I use XMing (or VcxSrv sometimes) to open graphical applications. I had multiple trouble to make it works but by googling my problems and playing with xauth I can now remotly open my QML application. **BUT** When running my application with a normal user I get : `KiTTY X11 proxy: Unsupported authorisation protocol QXcbConnection: Could not connect to display localhost:10.0` I noticed that the error message say **Unsupported** (a lot of SO question are about **Wrong** protocol) **AND** I can only open it in root (sudo does't work here, I need to su), and I got multiple errors : > failed to get the current screen resources WARNING: Application /home/user/QMLapp/app calling GLX 1.3 function "glXCreatePbuffer" when GLX 1.3 is not supported! This is an application bug! QXcbConnection: XCB error: 170 (Unknown), sequence: 163, resource id: 90, major code: 146 (Unknown), minor code: 20 **Note :** glxinfo seems fine and direct rendering is activated. glxgeers works fine too and don't need to be root to work **First question** : Can I easily upgrade my GLX ? **Second question** : Why it only works in root ?