1st, as webcontroluser said, check you have no reference to IE Web Control installed in your GAC, and use:
<%@ Register TagPrefix="ie" Namespace="Microsoft.Web.UI.WebControls" Assembly="Microsoft.Web.UI.WebControls" %>
2nd, be sure you and your host have the same Framework 1.x version
You can add this in your web.config:
<configuration>
<startup>
<requiredRuntime version="v1.0.3705"/>
<supportedRuntime version="v1.1.4322"/>
</startup>
</configuration>
....according to your required and supported versions
3rd, check webctrl_client\1_0 dir is under your remote site root.
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