Hi, I'm getting the following error after upgrading to 8, my page tab worked fine in version 7.
The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).
Do you have <%= %> anywhere in the page template? Good chance that is causing the error. You'd need to do a Page.DataBind() on the page load for that template. You could add this in the <script runat="server"> tag at the top of the page template.
A little more info... this is from the home page default.aspx
Yup that solved the issue, I had those characters in one of my master pages. But now I'm getting the following error in a subpage...
Only one instance of a ScriptManager can be added to the page.
That would mean that you have more than one instance added. Check the front end of the page and see if the page is inheriting from any other page. If there is one in your master page, I would comment it out and see if that gets rid of the issue.
Little update... the scriptmanager error only shows while logged into the cms. If I log out of the cms and not in preview mode. I don't see the error. My site works fine when not logged in the cms, but if logged in, things don't quite work right.
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