# Actionscript doesn't work

**URL:** <https://forum.kirupa.com/t/actionscript-doesnt-work/321649>\
**Category:** Uncategorized\
**Created:** [April 26, 2011, 6:00pm UTC](https://forum.kirupa.com/t/actionscript-doesnt-work/321649 "2011-04-26T18:00:57Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![docco](https://avatars.discourse-cdn.com/v4/letter/d/dbc845/32.png) [@docco](https://forum.kirupa.com/u/docco)\
**Post date:** [April 26, 2011, 6:00pm UTC](https://forum.kirupa.com/t/actionscript-doesnt-work/321649/1 "2011-04-26T18:00:57Z")

</div>

I have a swf file with 50 frames  
-At frame 50 I put an actionscript:  
this.addEventListener(MouseEvent.MOUSE\_OVER,gotoAndPlay(25),false);

but when preview, the flash forgets mouse event, it plays from 1-50 then loop 25-50.  
with error: TypeError: Error #2007: Parameter listener must be non-null.  
What’s wrong here?  
Hope someone help me to point out