Lee, I finally isolated it to a bug in the DNN Core. I (used to) create my Portals on my D:\ drive in a directory called Portals. Simple enough and quite intuitive, right? However, the directory name Portals causes the error and can be easily duplicated by creating a fresh install of DNN in (let's say) D:\Portals\MyWebsite. This has been plaguing me 6 to 9 months and I just recently isolated the bug.