No new guide data for 30 days - S03 error

I got a notice today that my Roamio Pro hasn't been able to get data for 30 days, and when I check the status screen it says Failed..SO3 error. I'm given to understand this means the channel guide database is corrupt, and new data won't load.

It connects fine, downloads the data OK, takes a looooong time to load (I gave up watching after an hour at 40%), but in the end it fails with the SO3 error.

I've read suggestions for other models , including KickStart 57, deleting the guide data and...

No new guide data for 30 days - S03 error

No new guide data for 30 days - S03 error