i tried whatching a video......

.....but for some reason it wont play ive downloaded it but it will not play ive tied everything could you please explain to me what to do?

Probably its your codec.

K-lite Codec

Have you tried redownload the video?

First off, it's "watching". Secondly, this belongs in the Technology section, not here that's for overall site functions.

First off what player are you using for example mpc(meda player classic), VLC,..etc.

Yarr, you sure the player supports the video format on the movie you downloaded?

Re-download the video, or use a good Video Player...