Re: Cannot send/receive emails with Thunderbird anymore
Are you able to send and view email using the webmail interface? Can you try using another client (such as Outlook) to see if that works?
If no desktop client will connect, then they could have done something that hosed your mailbox...which only they can fix. If you can connect to the mailbox (and especially if Outlook works) then there is something wrong your Thunderbird client. Maybe uninstall/reinstall will fix that.