I was on my PC and I noticed it was running a little slower from when I first purchased it, it was running 100% perfect except I thought I was noticing it to be a tiny bit slower so I thought it wouldn't hurt to do a system restore to bring it BACK to the POINT it was when I first bought the computer. During the process of restoring I received an error that says -- ( Your PC ran into a problem and needs to restart. )  StopCode 0xc000021a    -- this error has terminated my PC and I can't turn it on anymore. I have attempted to troubleshoot and when I click system restore there is no more saved restore points to select. I tried the other option of Resetting the PC to it's  first current state and that process has failed multiple times. I have tried two YouTube videos that GAVE me multiple commands to type in the command prompt and I tried them all and each time I restart my PC I get the same error and now the computer does not WORK anymore. ---- I need help to fix this problem, I regret attempting to restore the PC because it was working fine before I did anything.