Out of nowhere today, Oculus Rift owners around the world found that their virtual reality headset wouldn't work due to a small error. "Can't reach Oculus runtime service" is the message that everyone trying to make use of their headset saw. Oculus' FAQ suggests restarting the software and restarting the hardware, neither of which seemed to do much good. The Oculus forums filled up with people complaining about the issue, with several digging into the Oculus files to see if there was anything indicating why a global glitch would occur. Sure enough, users have found and subsequently hypothesized a security certificate for the software expired today and was seemingly not renewed. Software uses security certificates to validate integrity with websites in order to prevent fraud or malicious use. Oculus has tweeted an acknowledgement of the issue, stating "We’re aware of an issue impacting people’s ability to use Rift’s software, and we’re working to fix the problem. Please visit http://ocul.us/RiftRuntime for the latest—thanks for your patience!"