I sent emails this morning and all of a sudden they won't send. I AM receiving emails. Desktop use. Spectrum is internet provider and they confirmed that my settings are correct. Can send and receive on both phone and Spectrum webmail site. Problem appears to be only with desktop program. Have updated Thunderbird to most recent version. Norton antivirus is in tact.

Is Thunderbird server having problems?? (essentially, is this a "you" problem that's hanging me up or is it my box?)