Operating System & Device Fixes

Every operating system gates camera access at the OS level before any browser or app ever gets a chance to request it, and each one implements this gate completely differently. Windows exposes a dedicated Settings toggle plus a separate "desktop apps" permission layer, with Device Manager sitting underneath as the actual hardware-detection layer. macOS handles this through System Settings' Privacy & Security pane, with its own daemon (VDCAssistant) managing the actual hardware handoff — a daemon that's genuinely prone to getting stuck after sleep/wake cycles in a way Windows' equivalent isn't. ChromeOS, Android, and iOS each have their own further-simplified or further-restricted versions of the same underlying idea, and Linux exposes the rawest version of all through V4L2 device permissions directly.

The practical consequence is that a fix which works on one platform is frequently meaningless on another — "reset Chrome's site permission" does nothing if the actual block is a Windows privacy toggle, and "check System Settings" is irrelevant on a machine running Windows. This category is organized by platform specifically so you can jump straight to the permission architecture that actually applies to your device, rather than working through generic advice written for a different operating system's completely different settings layout.

Within each platform section, articles are ordered from the most common cause to the more specific ones, so working through them roughly in order — rather than jumping straight to whichever sounds most dramatic — tends to find the actual cause faster.

It's also worth knowing that mobile platforms add their own further wrinkle: Android and iOS both require HTTPS before a site can even request camera access at all, silently failing on plain HTTP with no error message explaining why — a genuinely common, easy-to-miss cause on phones specifically that has no real equivalent concern anywhere on desktop testing at all, regardless of which specific platform you're using.