Notifications from Email Events are not getting sent out and the workflow goes into an error state with the following error shown on K2 Workspace > Error Profiles:



From the K2 Host Server logs, the error below is logged at the same time: 

"SourceCode.Workflow.Common.SmtpMail","0 SMTP mail send failure: Verify the SMTP connection strings are correct and that SMTP is working properly. Exception: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.1 Client was not authenticated"

Troubleshooting Steps

To resolve the issue, please complete the following steps:

1. Open the ConnectionStringEditor.exe in [Drive]:\Program Files (x86)\K2 blackpearl\Host Server\Bin

2. Modify each SMTP connection string and set Authentication to 'Plain' and input the UserID and Password used to authenticate with.