Have you configured the UserControlSample as virtual directory in your IIS?
If yes, please try the steps below:
If you can, on the server, go to the following directory via the Command Prompt :
C:\WINNT\Microsoft.NET\Framework\v1.1.4322
And lauch the following command :
aspnet_regiis.exe -i
This command recreate the links between ASP.Net extensions, the ASP.Net ISAPI and IIS.
asp.net Chat http://cutesoft.net/ASP.NET+Chat/default.aspx
Web Messenger: http://cutesoft.net/Web-Messenger/default.aspx
asp.net wysiwyg editor: http://cutesoft.net/ASP.NET+WYSIWYG+Editor/default.aspx
asp wysiwyg html editor: http://cutesoft.net/ASP
asp.net Image Gallery: http://cutesoft.net/ASP.NET+Image+Gallery/default.aspx
Live Support: http://cutesoft.net/live-support/default.aspx