forums.asp.net/t/1334532.aspx

There are a few hidden files created under the local settings folder below that once removed seemed to correct the problem.  4 files to be exact all ending with .tbd.

C:\Documents and Settings\USER_NAME\Local Settings\Application Data\Microsoft\VisualStudio\9.0

thefrozencoder.ca/post/2009/06/27/VS-2008-Duplicate-Toolbox-Items.aspx

The fix was to close VS and delete the 4 *.tbd files located @ C:\Documents and Settings\USER_NAME\Local Settings\Application Data\Microsoft\VisualStudio\9.0\ (under XP / Win2k3) or C:\Users\USER_NAME\AppData\Local\Microsoft\VisualStudio\9.0\ (under Vista / Win2k8 / Win7)