HmdError_None (0) - There was no error

HmdError_Unknown (1) - There was an unknown error

HmdError_Init_InstallationNotFound (100) - The installation folder specified in the path registry doesn't exist.

HmdError_Init_InstallationCorrupt (101) - The installation folder specified in the path registry has no bin folder.

HmdError_Init_VRClientDLLNotFound (102) - The bin folder has no vrclient.dll (or system-appropriate dynamic library.)

HmdError_Init_FileNotFound (103) - A driver could not be loaded.

HmdError_Init_FactoryNotFound (104) - The factory function in vrclient.dll could not be found. Is vrclient.dll corrupt?

HmdError_Init_InterfaceNotFound (105) - The specific interface function requested by VR_Init or VR_GetGenericInterface could not be found. Is the SDK being used newer than the installed runtime?

HmdError_Init_InvalidInterface (106) - This error code is currently unused.

HmdError_Init_UserConfigDirectoryInvalid (107) - The config directory specified in the path registry was not writable.

HmdError_Init_HmdNotFound (108) - Either no HMD was attached to the system or the HMD could not be initialized.

HmdError_Init_NotInitialized (109) - VR_GetGenericInterface will return this error if it is called before VR_Init or after VR_Shutdown.

HmdError_Init_PathRegistryNotFound (110) - The VR path registry file could not be read. Reinstall the OpenVR runtime (or the SteamVR application on Steam.)

HmdError_Init_NoConfigPath (111) - The config path was not specified in the path registry.

HmdError_Init_NoLogPath (112) - The log path was not specified in the path registry.

HmdError_Init_PathRegistryNotWritable (113) - The VR path registry could not be written.

HmdError_Driver_Failed (200) - A driver failed to initialize. This is an internal error.

HmdError_Driver_Unknown (201) - A driver failed for an unknown reason. This is an internal error.

HmdError_Driver_HmdUnknown (202) - A driver did not detect an HMD. This is an internal error.

HmdError_Driver_NotLoaded (203) - A driver was not loaded before requests were made from that driver. This is an internal error.

HmdError_Driver_RuntimeOutOfDate (204) - For drivers with a runtime of their own, that runtime needs to be updated.

HmdError_Driver_HmdInUse (205) - Another non-OpenVR application is using the HMD.

HmdError_IPC_ServerInitFailed (300) - OpenVR was unable to start vrserver.

HmdError_IPC_ConnectFailed (301) - After repeated attempts, OpenVR was unable to connect to vrserver or vrcompositor.

HmdError_IPC_SharedStateInitFailed (302) - Shared memory with vrserver or vrcompositor could not be opened.

HmdError_IPC_CompositorInitFailed (303) - OpenVR was unable to start vrcompositor.

HmdError_IPC_MutexInitFailed (304) - OpenVR was unable to create a mutex to communicate with vrcompositor.

HmdError_VendorSpecific_UnableToConnectToOculusRuntime (1000) - The connection to the Oculus runtime failed for an unknown reason.

HmdError_Steam_SteamInstallationNotFound (2000) - This error is not currently used.