Efax problems

I use the web-based efax to fax, and it has been working great. All of a
sudden, it won't work: I cannot pull up a Word document and efax it by using
efax as the printer. It HAD been working fine. I've done everything efax
asked, at least twice, including uninstall and install. On their end, they
say I'm up and running and verified. They are telling me it's a problem with
Microsoft firewalls. Never had the problem in the past, and went in and
turned off the firewall. No help. Also, have always had to turn off Norton.
Has anyone else experienced this problem with efax?