I have downloaded the project provided by Hristo on 13 Jan 2016. Please refer to the attached gif file illustrating the behavior on my end with the latest version.
The three added columns remain in the right grid control. As to the specified changes, I would like to note that GridViewTextBoxColumn doesn't offer a UniqueName property.
Could you please specify what are the exact changes that you made in the code or at design time in the prject which results in the multiple columns displayed on your end with Hristo's project?
I am looking forward to your reply.
Dess | Tech Support Engineer, Sr.
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