Thanks popowich for your reply. I think it's yahoo that is having issues with their DNS servers or networking.
As today the traceroute works and therefore sending email works:
C:\Program Files\Support Tools>nslookup smtp.bizmail.yahoo.com
Server: dns.rnc.net.cable.rogers.com
Address...
How many people are experiencing yahoo SMTP email server connection problems?
I use the business service smtp.bizmail.yahoo.com and have been having connection problems for 2 weeks. Spoke with Yahoo support and they gave a reason 'DNS caching problems' at my service provider as the issue...
