W10 AU takes webcams out of commission.

[whoololon]

As stated in this article on ArsTechnica, it seems that the latest update to the new operating system from Redmond leaves both USB and IP-connected webcams unusable.
According to the explanation, the problem lies in how the OS manages access to the resources of the devices in question; previously, the device was used exclusively by a single application, preventing access to others that needed it unless the first one was closed.
W10, on the other hand, does allow sharing access to such devices simultaneously, implementing what has come to be called Windows Camera Frame Server, incorporated in version 1607.
It is this service, whose malfunction is due to an unreported error regarding data compression, that is causing the problem.

[Yorus]

Wow, I can't remember a Windows with so many problems. That particular one doesn't affect me, but it already scares me to start Windows, in case it messes up Linux Mint as well, like TH2 did to me.

[whoololon]

Waiting for the patch to fix the mess from Microsoft, an unofficial solution to the problem has been published:
(WccfTech's cut-paste)

• First, run the registry editor. ("Win+R", type regedit and press "Enter")
• Expand HKEY_LOCAL_MACHINE > SOFTWARE > Microsoft > Windows Media Foundation > Platform.
• Inside Platform we right-click to access the New menu and select DWORD Value (32-bit)
• Name the value as EnableFrameServerMode and give it a value of 0.

From here it's only for the 64-bit version of Windows.

• Expand HKEY_LOCAL_MACHINE > SOFTWARE > WOW6432Node > Microsoft > Windows Media Foundation > Platform
• Just like before, we add a DWORD value and name it EnableFrameServerMode and give it a value of 0.

Once we restart, we should be able to access our cameras normally.