That's a lie, of course. They won't be doing anything like that because it is
still far, far easier to stick to the protection they get from the DMCA by
responding only when they get a complaint about shared files, not downloading.

It is typical of cable companies to show such utter contempt of their internet
customers by making such transparent lies, assuming all of their customers are
so easy to fool and manipulate. They should have just stuck with their little
TV broadcasting monopolies because their technical and people skills have
never come even halfway to the levels of a real internet service provider,
even after a decade of experience.

Anyway, you're not in any trouble. Those DMCA complaints are just
routine paper shuffling to Comcast and you can be sure they've already
forgotten about it, since they handle dozens every week and don't have the
manpower to waste on such things.

Just stop sharing anything under copyright and don't reply to any of those
emails at all. To do so gives lawyers an opening to exploit, should they
choose to get rude. Your reply could even find it's way back to the
lawsuit-happy MAFIAA drones, revealing your identity and giving them a
chance to extort a few thousand bucks to "avoid" one of their bogus lawsuits
(none of which have ever succeeded in a real court under a real judge, but
don't expect them to admit to it).



The only way this could have happened is if you were sharing the file by mistake.
Here are a couple of things you can do to prevent these accidental leaks:

Firstly, go into Setup/Uploads and turn off "Enable Partial File Sharing".
That will stop files from leaking out while you are still downloading them.

Secondly, go to the Library view, find your downloads folder in the tree view
on the left side, right-click and click on "Shared" to turn that off. Now your
most recently downloaded files won't be shared until you say so.