Itunes Painfully Slow on Windows 10

I've been struggling for days with this recent behavior. I've cleared my Music directory; I've removed and reinstalled itunes; I've tried removing all Apple installed programs (icloud, ipod, bonjour, apple update) and reinstalled itunes. But it persists. Startup takes forever.

It must be something to do with my profile. When itunes finally does get started accessing my profile is an awfully slow process. It takes several minutes for my profile to show.

None of the advice I've seen has helped.

ps. my itunes subscription includes match and music.