Why can I receive but not send email in Outlook 2003? New Dell Optiplex w/ Norton and Verizon DSL

[ptobinPR]

I have a 2 month old Dell Optiplex computer with Windows XP; and use
Verizon DSL.

All my settings are correct, I've double and triple checked. There are
no Verizon problems.
It appears as if all actions are completed, yet they emails do not
send. I use Norton Internet Security Suite, turning it off doesn't
help, they don't send. I have the settings at medium.

A computer technician found yesterday I had PST errors (but none in the
outlook email files themselves) and did a repair generated by the
computer.

Today, late in the day, e-mails were stuck in my outbox. I have to
turn off my computer and turn it on again to be able to send email
messages.

Other problems with computer: Memory can not be read errors upon
shutdown. My mouse also doesn't work in word periodically - I can't
use the mouse to cut and paste or bold words.

Any Ideas?

Thanks.

 

[ptobinPR]

By the way: I get NO error messages when I'm trying to send out
emails. I read an older post that seemed to indicate that a Norton
update was the culprit in that individual's inability to send emails.
This is periodic, and strangely seems to come late in the day.