Unity 3D HTC vive - Assertion failed on expression

Questions & Answers
1

HI all,

I’ve used Unity for a few years now making the odd project and I recently got my HTC Vive.

Everything is working great, most nearly all games are working fine.

However, when trying to use Unity with the VR headset I just keep getting the same error.

Assertion failed on expression: ‘(ID3D11Device *)s_Device’

I’ve tried the SteamVR asset but it produces the same error.
I’ve also tried the link following from Unity3D which is for the oculus but it states “Other VR Head Mounted Displays (HMDs) will also work with Unity, such as the HTC Vive…,”.

I’m on Windows 7 64bit SP1.

Unity 3D version 5.5.1.

Direct X 11 (According to dxdiag)

AMD Radeon R9 200 Series

System Memory 16 GB

Driver version 17.1.1

I’ve set my VR Headset Compatibility to OpenVR in Edit → Project Settings → Player Settings.

Tried Restarting Unity, restarting PC.

The SteamVR tool is running.

Any ideas?

Thanks!

2

I assume you recently updated to 5.5.1?

I was having this same issue. It seems to be an issue or bug with Unity 5.5.1.

I’d recommend just downgrading by going here: Download Archive

Download and install 5.5.0. Once I did that it fixed this problem for me.