Created Unassigned: 0x800a138f error [27732]

seven days ago stopped working project using AjCnTk.
On board: Visual Studio Express for Web 2012, AjaxControlToolkit 7.1213 with other unnecessary things.
Go out: TextBoxWatermarkExtender, FilteredTextBoxExtender and other extenders. D'nt work dragpanelextention.
What happ?
I'm reinstall VS, AjCnTk - nothing! "Don't UI"!
Kill FrameWork 4.5.1. - nothing!
the impression that I had one suddenly broke.
Please! What to do?