Error only appears on Internet. Help please

programming flash
1

Dear all,

I am getting an Error #1010 when I test my swf file on Internet. Off line everything is ok but on my site I got the error. According to Adobe this error means:

TypeError: Error #1010: A term is undefined and has no properties.

This error can occur if you try to access a property of an object that does not exist. For example: 
var obj:Object = new Object();
obj.a = "foo";
trace(obj.b.prop);

But it should not appear also when I test it directly from Flash?

Thanks in advance