1. Can you access the email server? Have you tried to telnet the mail server? Does it require authentication?
We're you(ip address) already allowed by the mail server to send?
2. Did you see any errors such as run-time errors etc?
3. Have you tried restarting the alert services via the Orion Service Manager?
4. If problem still persists, try repairing the installed solarwinds and apply the latest service pack.
5. If you still have the same problem, try raising a case at solarwinds.com using your customerid and password.
Hope I answered some.
Please open a ticket with our Support staff. They will happily help you resolve this problem.