For some reason, I cannot remove bookmarks on AJAX Client (User and shared bookmarks) . Tried removing using different users and sessions but with no avail. This behavior seems to apply only to QV10 (QV9 works well).
It's definitely a problem in AJAX and the IE plugin. As far as I can tell, the only way to remove the bookmark is to find its object id from within the client, then remove that object from within the QEMC (Documents - User Documents - Server Objects).
