Update: I found a solution:
http://geekswithblogs.net/cicorias/archive/2007/10/10/Restoring-Missing-Toolbox-Items-in-Visual-Studio-2005---just.aspxI clicked on a class in the class designer VS2005 (C#) and then clicked on toolbox, and what was displayed is:
#13119
There are no usable controls in this group. Drag an item onto this text to add it to the toolbox.
???
.·*´¨)
.·`TCH
(..·*
010000110101001101101000011000010111001001110000010011110111001001000010011101010111001101110100
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