The SMTP Tester checks whether the mail server of the customer is correctly configured, so that upon activation of the seppmail.cloud service everything works as intended. There are a number of options.

The test E-mail is sent from the address "smtptest@seppmail.io". In addition, the SPF test is done with the address "smtptest@spffail.seppmail.io".

 

Field

Description

anchor link Recipient:

Enter the recipient, either as E-mail address(es) or as domain

(if only the domain is given, typical default E-mail addresses will be tested, for example "postmaster@<domain>" and also a randomly generated E-mail address "sepp.<random>@<domain>").

anchor link Relay Name

Enter the name of the mail server, for example "mail.<domain>"

anchor link SMTP Port

Default: 25

(for Exchange 2013 and newer versions: 2525)

anchor link E-Mail Delivery

There are three selection options

  • "Don't send E-mail": the test result is not sent per E-mail.
  • "Send default E-mail": the test result will be sent in a pre-defined E-mail template.
  • "Send custom E-mail": opens an entry mask for this E-mail.

anchor link Disable TLS

"Transport Security Layer": normally, the encryption on the transport layer is always active. If there are problems, TLS can be switched off as a test.

anchor link Test Exchange 2013

Tests Exchange 2013 and newer versions to see if recipient filtering is enabled. For this purpose, an E-mail is sent to a random E-mail address.

If no error is returned, for example, a wildcard configuration may be present. On the one hand, this can lead to a higher number of E-mails in the invoice, on the other hand, it is unclear what happens to the E-mail (some mail servers send it back, which leads to a loop).

Special features here: Exchange 2013 initially receives every mail without testing and only reports at the end that it could not be delivered. Reception is done by default at port 2525. To avoid problems here, SEPPmail recommends a direct connection between the seppmail.cloud and the Exchange Backend Server.

anchor link Test SPF

Tests whether the customer server itself checks for SPF, meaning it has its own spoofing protection enabled. If so, this must be turned off, otherwise it will cause problems with the seppmail.cloud. See also the dedicated SPF Tester.

anchor link Test Open Relay

Checks for the existence of a so-called open relay, which means that the mail server allows E-mails to be sent from any sender to any recipient. This is critical and should definitely be fixed.

 

Via Run Test, the test is started.

Via the Share test results button empty, the result of the test is copied to the clipboard as a URL and can thus be passed on to other people.

Depending on the selected option, the test results show the following sections (for the full list of fields see SMTP tests and explanations):

  • SMTP Base Test: Overview of the most important results incl. TLS test (this area exists twice for instances in Switzerland, as the test is carried out from two different IPs)
  • Exchange2013
  • Test SPF
  • Open Relay
  • DNS Tests and Test Evaluation: test results of the DNS Record entries

The following columns are available:

Column

Meaning

anchor link # Number

Consecutive number per section

anchor link Test

Tested parameter

anchor link Status

Result with corresponding symbol

  • green checkmark empty - Okay  
  • yellow light bulb empty - Info  
  • orange exclamation mark empty - Warning  
  • red cross empty - Error  

anchor link Return value

Detailed return value from the SMTP log

anchor link Explanation

Detailed explanation, see also SMTP tests and explanations