OME 2.1 Email Alerts Error

Hello,

I upgraded our OME server to version 2.1 last week.  It was simply an upgrade of existing software and database (after taking backup of database).

Everything appeared smooth until we noticed that email alerts were not being sent out on servers that had been down for patching.  After further investigating and trying to send test emails in the Alerts using Test Action... I saw in the logs the following error:

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * EXCEPTION * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *  12/07/2015 09:56:30  Unable to send the email.  System.Net.Mail.SmtpException: Failure sending mail. ---> System.IO.IOException: Unable to read data from the transport connection: net_io_connectionclosed.    at System.Net.Mail.SmtpReplyReaderFactory.ProcessRead(Byte[] buffer, Int32 offset, Int32 read, Boolean readLine)    at System.Net.Mail.SmtpReplyReaderFactory.ReadLines(SmtpReplyReader caller, Boolean oneLine)    at System.Net.Mail.SmtpReplyReaderFactory.ReadLine(SmtpReplyReader caller)    at System.Net.Mail.SmtpConnection.GetConnection(ServicePoint servicePoint)    at System.Net.Mail.SmtpClient.Send(MailMessage message)    --- End of inner exception stack trace ---    at System.Net.Mail.SmtpClient.Send(MailMessage message)    at sendmail.Program.Main(String[] args)  System.IO.IOException: Unable to read data from the transport connection: net_io_connectionclosed.    at System.Net.Mail.SmtpReplyReaderFactory.ProcessRead(Byte[] buffer, Int32 offset, Int32 read, Boolean readLine)    at System.Net.Mail.SmtpReplyReaderFactory.ReadLines(SmtpReplyReader caller, Boolean oneLine)    at System.Net.Mail.SmtpReplyReaderFactory.ReadLine(SmtpReplyReader caller)    at System.Net.Mail.SmtpConnection.GetConnection(ServicePoint servicePoint)    at System.Net.Mail.SmtpClient.Send(MailMessage message) ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 

Any ideas on how to fix this?  I've tried changing email servers, including an internal email server and an external google server but the error is the same.

Thank you for your help.