what to do before calling

A Windows Blue Screen means something on your PC has gone terribly wrong.  A majority of the time Blue Screens are caused by hardware errors.   This includes (and is not limited to) defective computer memory, a failing system board (watch for capacitor plague), a hard drive reaching the end of its life (or a catastrophic failure - sometimes called a head crash or simply bad blocks).   The failure of cooling fans on the CPU, Chipset, or Power Supply can cause overheating of internal components, which can cause a blue screen.

Bad shutdowns and corrupted Windows registries can do this, as well as installing hardware with bad or bug-ridden hardware drivers. In this instance, it may be possible to restore normal operation by pressing F8 at boot time and picking "Last Known Good Configuration."

When this occurs it is very helpful to write down the error message! - just the first few lines is usually sufficient, as shown below:  Note your error message(s) are usually different.

Frequently updated information on Blue Screen Stop Errors
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