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Troubleshooting errors on sending mail
Who is this article for?Users who encounter errors when adding/updating FBA identities and IT Administrators finding mail-related errors in Robot logs.
IT Administrator permissions are required to resolve these problems.
The system is able to send emails when automatic triggers (such as action notifications) and manual triggers (such as password reset emails) are met.
This article explores troubleshooting error messages that can appear either in the desktop application or in the Robot service log.
1. Troubleshooting errors
The first question to ask is whether the system has been behaving as expected up until now.
If the system has been sending emails with no problem and suddenly you are seeing error messages, then something has changed. If the application server configuration has not been updated, this indicates that something has changed at the mail server, like a change in a setting or expired password.
The next step here is normally to contact your local IT team and work through the error with them.
1.1. Troubleshooting connectivity errors
This section lists common errors relating to connections and their causes.
If the client or Robot cannot connect to a server then you are likely to see one of the following messages:
- No connection could be made because the target machine actively refused it
| Causes | Troubleshooting |
| Application is connecting to the wrong port. | Verify the port the SMTP service is using to listen, and check the application configuration. |
| Mail server is online, but the SMTP service is not listening. | Ensure that the mail service is running and that no firewalls are blocking the listening port. |
- The remote name could not be resolved: 'server.domain.com'
| Cause | Troubleshooting |
| Application server cannot resolve the name of the mail server specified in the configuration files. | This is either a DNS-related issue, or the name of the server specified in the application config is not correct. |
- Unable to read data from the transport connection: net_io_connectionclosed.
| Cause | Troubleshooting |
|
Server requires an SSL connection to port 587, but the application is configured to connect to port 465. |
Check the settings that are expected by the mail server Administrator, and configure the application to match. |
- A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond
| Cause | Troubleshooting |
|
Server expects an SSL connection to port 587, but the application is configured to connect the wrong port. |
Check the settings that are expected by the mail server Administrator, and configure the application to match. |
- An existing connection was forcibly closed by the remote host
| Cause | Troubleshooting |
|
Client is configured to connect to SMTP port 25 using SSL. |
Check the settings that are expected by the mail server Administrator, and configure the application to match. |
1.2. Troubleshooting SMTP errors
This section lists errors that you might see if the application is able to connect to an SMTP server but experiences a problem.
- The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.3 Client was not authenticated
| Cause | Troubleshooting |
| Incorrect username/password. |
Verify that the application is configured to use the correct credentials. At the mail server, check that the mailbox user account is not locked or that the password has expired. Review logs on the mail server for more information about the failed login, and then validate against the application configuration. |
- The SMTP server requires a secure connection or the client was not authenticated.
The server response was: 5.7.0 Must issue a STARTTLS command first.
| Cause | Troubleshooting |
|
Server requires authentication, but the application is configured for anonymous connection to port 25. |
Check the settings that are expected by the mail server administrator, and configure the application to match. |
|
SMTP server requires an SSL connection, but the application is configured with SSL = false. |
Set SSL = true in application configuration . |
-
Gmail: The SMTP server requires a secure connection or the client was not authenticated.
The server response was: 5.7.0 Authentication Required.
| Cause | Troubleshooting |
| If connecting to a Gmail account, this is the error you will see if you are using the wrong username or password or are using the mailbox login instead of an app password. | Specify the correct username and password in application configuration. See this article for more information. |
- The server response was: 5.7.54 SMTP; Unable to relay recipient in non-accepted domain
| Cause | Troubleshooting |
| SMTP server is not allowed to relay to to the recipient's domain. | SMTP server Administrator should troubleshoot relaying for this domain. |
- The SMTP server requires a secure connection or the client was not authenticated.
The server response was: 5.7.57 Client not authenticated to send mail. Error: 535 5.7.139 Authentication unsuccessful, basic authentication is disabled.
| Cause | Troubleshooting |
| This error is returned if the application is configured to use a username and password but the mail server has basic authentication disabled. | Ask the mail server Administrator to provide a mailbox that will allow basic authentication. |
-
Mailbox unavailable.
The server response was: 5.7.x Client does not have permissions to send as this sender
| Cause | Troubleshooting |
| The application is trying to send mail from an address that is prohibited by the mail server. This address might be different to the mailbox name. | Either update the mail server to allow the mailbox to send on behalf of the specified email address, or change the application configuration to use an allowable email address. |