Actually, it looks like the 404-Error may be occurring just when the PM page loads, versus backing up to it.
If I open up a new browser, and paste this in the Address Bar...
http://local.debbie/account/view-pm/incoming/4
...and hit <enter>, then I get an e-mailing saying there was a 404...
(I don't understand how a Page can load AND throw a 404-Error all at the same time?!)
Debbie