Vista Gadget SWF doesn't want Policy file anymore

We have developed a gadget application for Microsoft Vista one year ago,
gadget includes a swf file which loads data from our webserver,
so when client uses the gadget,
the address of swf is,
"file:///C:/Users/username/AppData/Lo...adgetSmall.swf"
so in regular,
if we don't prepare a policy file that gives permission from any swf that comes from any domain, the swf (so gadget) cannot load the data from our webserver,
in our tests that we made one year ago, we couldn't load data without using a policy file,
but one year later,
2 days before ,
when I was working I realized that policy file in the web server have been deleted 5 months ago (from iis log files, swf takes 404 when thet try to load policy file for 5 months),
I expect that gadgets should not work
but they are still working,
but how?
there is no policy file in our web server,
but the client swf,
which is in users' gadget file is able to load data from our servers,
In addition, the swf file that isused in gadget application doesnt work in a stand-alone application ( for example in a separate internet explorer, I got the following error in flash player logs

Warning: Failed to load policy file from http://xxx.xxx.xxx/crossdomain.xml
Error: Request for resource at http://xxx.xxx.xxxx/xxx/xxx.aspx by requestor from file:///C:/Users/xxx/AppData/Local/M...adgetSmall.swf is denied due to lack of policy file permissions.
)

I searched a lot, but I couldn't find anything,
yes there is no problem for me,
gadgets are working,
but only I'd like to learn, what have been changed, any comments will be appriciated..