BAD_POOL_CALLER, also known by the BSOD STOP code 0x000000C2 (or 0xC2), means that the current processor thread is making an invalid pool request.
Fix 'Bad Pool Caller Blue Screen' Error in Windows 10 [Updated]
What does that mean? It can indicate a situation where a piece of software is trying to use a processor thread that is not available because another program is using it. It can also mean that the thread does not exist at all.
In many cases, the 0xC2 Bad Pool Caller error indicates a problem with the device driver.
The error always appears on a STOP message, better known as a Blue Screen of Death (BSOD). You can see it when your computer first boots up, right after you log in, when you do something specific like play a video or open a program, or even right after a fresh install of Windows 10.