The Rook is allowed to pass through a controlled square. It's just the King that can't.
Don't feel bad, GM Viktor Korchnoi asked that of an arbiter during his candidate's match against Karpov. He was considered one of the top 5 players in the world at the time.
Thank you for your comment Dodger11 but I don't understand, so is it legal? And what do you mean with "controlled square"? And why when I was trying to do the next movement in the diagram, it didn't let me do that and it let me do any other movement. You can try if you want.
When I say controlled square I mean the King cannot pass through check, the Rook can.
Oh I understand now, thanks Dodger111, but then why when I was trying to do the next movement in the diagram, it didn't let me do that? AdamovYuri?
Pretty sure it's legal. I believe the king can't pass over a controlled square but the rook can, so O-O-O is fine.
Oh I understand now, thanks Dodger111, but then why when I was trying to do the next movement in the diagram, it didn't let me do that? AdamovYuri?
What is the next move you are trying to make after O-O-O ?
What is the next move in the diagram that you are refering to? The diagram only shows moves made, not moves not made. I have seen some chess sites on line that get the castling moves wrong. The thing to remember, is it is all about the King, not the Rook.
The next move I wanted to do is the castling, but the diagram didn't let me do that. You can try it if you want.
Yep it's legal. Rook can move through an attacked square but you lose the rook.
Okay, in seriousness, yes it's legal. There are many famous and humerous examples of players messing up castling.
For the file, make sure you manually have castling enabled:
The next move I wanted to do is the castling, but the diagram didn't let me do that. You can try it if you want.
That's because when you were setting the position you didn't allow castling:
If you allow castling everything works
Oups, I was late 
Oh I see, now all is clear, thank you everyone!
The next move I wanted to do is the castling, but the diagram didn't let me do that. You can try it if you want.
What do you mean the next move you want to allow is the castling? You said it WAS allowed, and then you coulndn't make your next move, which would be what?
The next movement of this was a castling from white, I could't show it in the graphic because it didn't let me do that. So my question is? Is it a bug/problem for chess.com?
This was a real game two days ago and I posted a comment on that:
"How is possible the movement 23 white (O-O-O)? I mean, my bishop is attacking the path of the castling, I knew that you cannot do castling while some piece is attacking the path of the castling."
Feel free to enter to my profile and watch the game, that game was vs telit on march 6