Actually the complete error message is “Your PC ran into a problem and needs to restart. You can restart. If you’d like to know more, you can search online later for this error: 0xc000021a
This error happened when we tried to rebuild the laptop Toshiba Portege M600 using MDT installer. We tried to refresh all the software because yesterday this laptop many times shut down automatically while the user using it.
Several possibility we need to check for the “Your PC ran into a problem and needs to restart” error:
1. Before we decided to rebuild using MDT server we suspect that the problem was because overheat on the system as we experience this problem quite often. However, this is not the case, although we already blow air using compressor to push the dust out of the laptop, the problem still persist.
2. Our second guess is corrupted hard drive. We replace the hard drive and boom we still see the same error Your PC ran into a problem and needs to restart. You can restart.
3. Our next suspect is memory, we remove the 2GB additional memory and see if this time we can finish rebuild software using MDT and it worked this time without any error.
So the problem was because additional RAM is broken. Using it’s 2GB original RAM is working fine.
If the memory is not your problem it could be system files corruption as suggested by Microsoft here:
Other possibility is conflicting driver, overheating, registry error as described on below website: