There is probably an "orphaned" toggle link somewhere on the page that is causing errors in the output. See this thread for instructions on how to deal with this:
If this doesn't help please mail a demo project illustrating the issue to support AT ec-software.com (replace the AT with @) and we will check it for you. If you are using a skin to publish your CHM file please also include the .hmskin skin file. We don't need the graphics initially, just the project itself in single-file .hmxz format. If you're using .hmxp currently you can save a single-file .hmxz copy with Save As... in the Application Menu (big button in the top left corner of the HM window). Choose the "Help Project (single file storage)" format, (.HMXZ in the description text on the right). Then just delete all the unnecessary topics in the project copy before mailing.
Regards,
Tim (EC Software Documentation & User Support)
Private support:
Please do not email or PM me with private support requests -- post to the forum directly.