For reasons that probably make sense to them, Optimum Online (the ISP part of Cablevision) uses totally insecure password-in-the-clear user authentication to the POP3 and SMTP servers. That’s marginally OK for access through their own cable network, but, should you access those servers through a different ISP, you’ve just exposed some sensitive bits to the Internet at large.
Disabling an account in Evolution requires removing one checkmark:
Edit → Preferences → Mail Accounts tab → uncheck the account → done!
Doing the same in Thunderbird, however, requires arcane knowledge and deft surgery, documented in the usual obscure forum post containing most of the information required to pull it off:
Edit → Preferences → Advanced tab → Config Editor button
server.server and find the
.name entry corresponding to the ISP account. Note the digit identifying the server, which in my case was 1:
server1 and find the number of the
mail.account.* entry with that string in the value field. In my case, that was
accountmanager to find the
mail.accountmanager.accounts entry and remove the account you found from the Value string.
Make a note of all that information, because you must un-futz the
accountmanager string to re-enable the account. Of course, if you add or remove any accounts before that, all bets are off.
There, now, wasn’t that fun?