If you’re having issues starting oculus on windows 7 after 1.39 update (after 25th July 2019) then here’s a solution:

(Taken from reddit)

Hi. Found a working solution for now. Im on Win7 and had the same issue of having my oculus bricked by a surprise update. Had the same “cant reach service” or whatever which I tried fixing by repairing (which required the bypassHotfixCheck because the setup is buggy), but that did nothing as the issue lies with the OVRServer_x64.exe file in oculus-runtime. Trying to running it gives an obscure error about the KERNEL.

However I managed to fix it.

Youll need an older version of your Support folder (from before you updated). I was lucky to have a system restore backup.

Copy the oculus-runtime and oculus-dash from the old to the new updated folder.

Started running and working fine.

Download files here:
http://www.mediafire.com/file/mt7xilf4dd41327/oculus_backup.rar/file

I had to disable any running oclulus processes and restart to get it to work but its working