problem with installing

So I've been asking about this problem for a while now and can never seem to get any straight answers... but I can't seem to install anything now... I'll get to download stuff, but once it's downloaded it'll never go to the part of moving it to the applications folder. So i'll double click on the actual icon and it'll come up as "quick player can't open because it's not a movie file" .... I'm very confused, if anyone can help out that would be awesome! thanks!

You haven't really given any information....
ie what did you try to download?
Did an installer show up on your desktop, or an installer package open in a finder window.
If an application icon appeared on your desktop at the end of download, and you drag it to the applications folder and try to open it what happens?

downloading stuff

Click to expand...

- could be downloading - applications - audio files - movie/video files. All are dealt to differently and also it can mean the need for additional applications eg trying to play a windows movie file Flip4Mac can help.

1. What Mac do you have?
2. What version of OS X are you using?
3. Exactly what are you downloading - file type - provide link - etc. Only one example to start with. Deal with and solve one issue at a time.

Without providing this specific information, you will get answers all over the place, with many of them having nothing to do with what your real problem may be. All the answers will only be guessing instead of specific help leading to even more frustration because the guessing game didn't help.