Hey all, I need some assistance to figure out how to fix this. I was trying to record something tonight and all of the sudden, there was an error saying on the Schedule part that the Cable Authentication Failed.
So I tried removing the Source of Youtube TV and readding it, but during the Verifying part of my correct email and password that is associated with my Youtube TV account, it said Cable Provider Authentication Failed
Here's a picture from it. Can someone help me out here to figure this out? Obviously, it won't let me click anything on that Sign In picture you all see here.
I too see the same message when I try to set up my YTTV subscription credential for TVE. Wish it was as easy as adding Direct TV. But I can't get it to work either.
Same error for me
Seeing the same, tried on a two different Google accounts without 2FA or passkeys (one account just created) both can sign in to nbc.com, but can't be added as a source.
Looks like the e-mail isn't being passed through to the login page. My guess is YTTV has changed it's login page layout and whatever scropts the Devs have in place don't conform to this new format.
That's a wild a$$ guess, I am not a programmer, I just play one on tv. 
I had a YTTV TVE channel recording that was delayed this morning because Channels DVR had to reauthenticate the network channel. It did start recording about 50 seconds late.
After seeing the posts here I tried manually selecting different YTTV TVE channels to watch in the DVR web UI player. Some errored out and some reauthenticated.
Tried playing the ones that errored out a few times and now they're working.
I always try this method and don't rescan channels or remove/add the TVE source.
If playing the channel errors out (due to your Provider or the Network site) and you rescan the channel, it most likely will fail and remove the channel from the guide.
Worked after upgrading to pre-release. Didn't work with the :tve docker tag pulled yesterday.
Mind sharing which pre-release version you downloaded? Sometimes it helps to identify the version if something behind the scenes was changed that fixed (or broke) a service. I try and update at least every other week unless something specific is called out in the release thread that I am dealing with.