I am guessing it is because you added a new field as well which the control
is bound to.
It is disabled since that field does not exist in the old XML.
You can add nodes with code but I am not sure how to do this.
You could try posting this question in the code section at
http://www.infopathdev.com

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Clay Fox / Microsoft InfoPath MVP
www.InfoPathDev.com / The InfoPath Authority / Downloads, Samples, How-To,
Experts, Forum
> Can somebody help me, why my new added control became disable when I open it
> in the existing form? Open it as new (blank) form is no problem.
> Is it any setting that cause the new added control disabled in old form?