I finally managed to make it work (yeehaw !) after spending hours messing around, uninstalling / reinstalling drivers of everything, softwares,  plugin things in different orders, .. without any success, here is what seems to make it work : I decided to try the wireless adapter with my "old" HTC Vive (non-pro) : first try : same error messages (208) I changed the Connection mode in the Vive Wireless application settings : The default setting was mode 1 : I got a strong signal, but SteamVR always returned the error 208. I changed to mode 2 : everything finally worked fine :-) mode 3 : OK as well returned to mode 1 (just for fun) ... : now it works (!)   Went back to my Vive Pro HMD : still no luck (error 208), even when changing conenction modes. I tried using the short cable provided with the wireless adapter (all my previous attempts were with the long cable originally provided with the Vive Pro) (strangely, after swapping the cable, and restarting Vive Wireless, Windows found a new device and reinstalled drivers for the Vive... and then it finally worked.   ... View more

Same problem here : can't change camera rate + cameras seems to be not aligned correctly: right camera is looking a bit higher than left camera, producing instant headache when activating cameras in chaperone... I had a long discussion by mail with support team, they made me reinstall everything, Vive drivers, change steamVR version, GPU drivers, change camera settings (rate..) ...  it took a week (1 mail / day) , to finally say that maybe my device has a problem and I should return it... But that I know that I'm not the only one with the same issue, I don't know what to do :-s     ... View more

I've just noticed that with Steam VR beta i have error 208. If I roll back to non-beta SteamVR I have error 108.   does it make sens ? ... View more

same problem here : Vive Pro Wireless driver installed correctly. HDM connected to Vive Wireless. All cable unplugged from computer. SteamVR error (208) : HMD not detected   help ! ... View more