Just wanted to follow up.
So I tried the drive with my phone USB adapter and the next box 3 asked me to format again. I said yes and yes to confirm.
Then I tried my guide and it was working and not frozen. My kid wanted to watch a movie on Netflix, so I left the box on and turned on Netflix on my smart TV, cartoon movie was about 90 min long. After it was over I exited Netflix, hoping to see a completed msg on the screen for the format, but nothing. I checked my guide and still working, checked my PVR and there it was, percent used went down about 30% , about what I expected for a 500gb add on. Maybe the msg came up and went away while the TV was on Netflix, not sure, but at least it works, now just to test some recordings.