There are a number of threads on this problem, I hope one helps. Here are two examples.
For more enter Runtime Error in the search and in the results you can limit the answers by typing in RoboHelp. As this is an application problem, it could be the cause is addressed in other forums though.
See www.grainge.org for RoboHelp and Authoring tips
Hi Peter -
You really are a wonderful guy, I hope you know that. Adobe should be paying you a consulting fee.
I went into add / remove programs, and it turned out I received an SMS package with a Windows update patch. Removing that allowed me to publish, which is great, since go live starts in 8 hours and I didn't have time to try and figure out how to clean up stuff manually. That would have been ugly (lots of changes).
Have a wonderful holiday season!