GfxDevice: creating device client; threaded=1 d3d: no support for this device type

My game server is made on Unity. In 3.4, my vps could run the server, but i upgraded the project to 3.5, vps can't run now.

VPS has no gfx device to run this but my game server doesn't need render,input etc. can i run it on 3.5? or i will go back to 3.4

console error:

Code (csharp):

1. GfxDevice: creating device client; threaded=1 d3d: no support for this device type (accelerated/ref)

it wasn't happen on 3.4

on 3.4 it could run and i got this message on the log

Code (csharp):

1. d3d: no support for this device type (accelerated/ref) D3D9 initialization failed, using OpenGL OpenGL: ......

and when I try to use -force-opengl on the server crashing by most of dll errors.