If I put an Captcha inside an asp.net UpdatePanel , the ImageStyle and TextBoxStyle and RefreshLinkStyle and AudioLinkStyle are not applied.
Stripping it down to a bare bones example (for an asp.net 3.5 site):
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<div>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<eo:Captcha runat="server" ID="Captcha1" PromptHtml="">
<ImageStyle CssText="border: solid 1px #c0c0c0; float: left;margin-right:5px;" />
<TextBoxStyle CssText="border: solid 1px #b7d9ed;margin-top:3px;padding-left:2px;padding-right:2px;padding-top:1px;padding-bottom:1px;width:146px;" />
<RefreshLinkStyle CssText="margin-left:5px;" />
<AudioLinkStyle CssText="margin-left:5px;margin-bottom:20px;" />
</eo:Captcha>
</ContentTemplate>
</asp:UpdatePanel>
</div>
<div>
<eo:Captcha runat="server" ID="Captcha2" PromptHtml="">
<ImageStyle CssText="border: solid 1px #c0c0c0; float: left;margin-right:5px;" />
<TextBoxStyle CssText="border: solid 1px #b7d9ed;margin-top:3px;padding-left:2px;padding-right:2px;padding-top:1px;padding-bottom:1px;width:146px;" />
<RefreshLinkStyle CssText="margin-left:5px;" />
<AudioLinkStyle CssText="margin-left:5px;margin-bottom:20px;" />
</eo:Captcha>
</div>
</form>
The first Captcha inside the UpdatePanel will have no Style but the second one outside the UpdatePanel does display the styling. If the UpatePanel is removed, both Captcha display the styling. (There is no other CSS on the page or in any attached style sheet.)
I've found the same problem here
http://www.essentialobjects.com/forum/postst6569_EditableLabel-inside-UpdatePanel-has-no-styling.aspx with EditableLabel which is fixed now.