After a couple of reboots, moving my library back to the C: Documents\calibre folder, and running a check on the database, it works again. That is great, though I hate it when I'm not sure why something quits working/starts working again. Not complaining though.
In the process of doing this I found an AutoHotkey script that not only hides the process, but hides the Qt error window:
PHP Code:
#NoTrayIcon ; To prevent momentary icon pop-up
run "C:\Program Files\calibre2\calibre-server.exe" –port 8080 –with-library C:\Users\jay-d\Documents\calibre,,hide
Save that code (modified for yourself of course) as an .ahk script. Works like a champ.