Tariq, sorry I don"t have answer to your question as I don't have P6. I just want to clear-out the original post of Terry and his own solution for the benefit of others who still perhaps don't understand the use of "Progress Override" and "Retained Logic".

Terry's issue is a classic example of an originally wrong logic or schedule (or perhaps not actually followed logic) that was overriden by actual progress, therefore, the occurence of the loop. He got the error everytime he clicks F9 as he had the "Progress Override" setting. Meaning, that the "Progress Override" setting or actual progress don't know how to Lie, thus, you need first to fix the problem before you can proceed or run the progressed schedule (simply due to a wrong logic, overriden by actual progress). 

Now, of course originally, you need the "Retained Logic" setting for your plan or schedule (simply because you have not yet started your project, therefore there's no actual data to consider). Again, actual data don't Lie, or can never be twisted (unlike Theory). 

I hope I had explained a bit clearly now (otherwise, sorry for my English). 

To continue, in order to fix the problem, of course you need to know where it emanates from. Therefore, going back to the original schedule or setting of "Retained Logic" (as what Terry did). From there, he sees exactly why the error happened, of course because of the wrong logic overriden by actual progress. 

Once the problem is fixed, then again, you have a fresh-progressed schedule. In my opinion, (from here) you may use either of the settings, depending on your evaluation, but then again, once new actual data comes, it may or may not deviate from your logics. So I guess you already know what to do? Hope this helps.

Just another fine real life example of why NOT to use "Progress Override"