Blank Replacement Value - image default?

[nier3]

Hi, when I create a new thread in my forum, if I don't put a picture of "preview" in custom Custom Thread Field (URL or File), I see as an error.

I tried to put this code in Blank Replacement Value:

Code:

<img src="http://mysite.com/forum/images/noimage.jpg" alt="" title="" />

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but it doesnt' work..I see still error, image of preview there isn't and if I use firebug on it I see:

Code:

<img src="/thumb150x120" width="" height="" alt="test">

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