This is a question which was asked on 2012-11-18 and has an accepted answer:

[Set "Selected Item" in multiselect RadComboBox](https://stackoverflow.com/q/13444846/1427849)

I found another answer which may be correct as accepted answer. 
If I add my answer, what will happen? Will this question become active again?
Can I get some reputation from this answer if it is correct and gets up-votes?