Could be a number of things but most likely if it works on your local machine but not on the server, it's a pathing issue. So you have all your flash related files in the same folder, correct? But are they all in the same folder as the web page? They do not have to be, any of the Flash related files can be in whatever folders you want, just remember to path the elements relative to the Web page, NOT the physical location of the Flash file. From an old post:
Almost always when it works on the local machine and not the server, it's a pathing problem.
You can put your Flash related files in whatever folders you want, they do not have to be in the root. But if sticking them in there worked, then you know that the issue was a pathing problem.
Just remember that paths become relative to the Web page on which those Flash files are used. So for example, if your .swf is in the flash/data folder and you use that .swf on a Web page in the root, you are in effect, removing that .swf from flash/data and putting it in root. So if the .swf is loading any related files (xml, etc), the path used inside the .swf to the .xml file has to be relative to it's new location in root and back down into flash/data. This is true even though when testing the .swf by itself, it can be inside flash/data and work just fine, since relative to it's location, the path is just fine, they are in the same folder. But if that same path is used when the .swf is placed on a page two folder levels up, the relative path has changed, the old "same folder" path will not work.
So just be sure that you use addresses relative to the final Web page locations (not physical file locations) and you can put the files wherever you want.
Eye for Video