What happened?

I was playing a quick game of chess with my computer when suddenly somthing stranged happened. the beginning was normal and looked like this (don't judge my computer i was playing on easy):

now just pretend that the white king was black. yes. the program turned my white king into a black king and told me "checkmate!" >:( you can see what strange things that happen when i play my computer. note also how it change colors of other pieces.  for example, g2, e5, a4, b5, c6, b7, f8, and e1.

52 views and i'm the only one who's commented

has any strange occurances happened like this to any of you?

People usually won't leave a comment just saying: "No that's never happened to me."

What the lack of constructive replies suggests is that no one else has experienced the problem you're talking about. Including me.

Also we would need more information to be helpful, the engine and GUI you were playing on/against being the most important.

What chess computer were you using? (so I can make sure I never use it)

when i had internet chess club (i do not have it anymore), i played against the computer on the hardest difficulty. i found a way to give up my pieces to bring a computer's pawn all the way to the seventh (second? i don't remember whether i was white or black) row where it checked my king. then, i castled (somehow, i managed to play this illegal move). the computer stopped moving (probably because it got confused). so, i waited for the computer's time to become zero. that was how i beat the computer at its greatest difficulty level multiple times.

Yes, it would be helpful to know what kind of computer you were using and what kind of chess program you were playing.

On my laptop running Win7, I can run Windows 3.11 under DOSBox (for nostalgia) and it has an old Windows chess program.  Sometimes it kind of does wonky things when you're about to win, like pop up with a window saying illegal move, and then crash.

sorry, i thought i was forgeting something... i use a windows xp (bleh) but unfortunatly, i couldn't tell you the program name, it just says, "chess" 

Sounds like the same old Windows 3.1 Chess program.  I don't remember if it's ever changed color of pieces on me before but that seems vaguely familiar.  I haven't played it for a while.  But I think the title on it just says "Chess."