Visual Web Developer Express 2010 doesn't save changes made to contents of Ajax Toolkit Tab Container in design view

When editing the contents of an AJAX Control Toolkit Tab Container in VWD Express 2010:

Sometimes the changes are saved ok, sometimes extremely slowly & sometimes not at all. A "page changed" asterisk in the name tab of the page appears briefly, but then disappears again.

Does anyone know anything about t开发者_开发技巧his, please?

Thanks! Vlad

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I found some unwanted and unclosed tags in among the HTML, inside the Tab Container. After deleting them, the problem stopped. No idea how they got there. Hope this helps someone...

Vlad