flash – calling externalinterface.call from embedded swf from another server is not working in Firefox – Education Career Blog

I have an index.html on server A.

In index.html I embed a swf from server B.

The swf contains a init with
flash.external.ExternalInterface.call(“alert”, “externalalert”);

When I run the swf on server B it works, when I run the swf through the index.html on server A I get an : Security sandbox violation: ExternalInterface caller…

It does work in IE.

Does anybody know what I’m doing wrong.



The fix is to add


in your AS code. ExternalInterface requires the allowDomain to be set when HTML-SWF cross-scripting is performed.

Note that you will also need to set allowScriptAccess="always" in the swf embed tags to allow cross-scripting.


You are doing nothing wrong. This is a restriction of the Flash player. Interacting between different domains is not allowed. You could try to use a crossdomain.xml. (But I do not know if this works you ExternalInterfaces).
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