Solve email and spam problems

Quotations, invoices, packing slips and other receipts can be emailed directly from Rentman. Unfortunately, it can happen that emails don't reach the customer. This article will explain what the cause could be and what you can do about it.

You can also change the sender address of your emails. Read our article on changing and verifying the sender address for your emails for more information.

Available for: Lite Classic Pro


There are several reasons why an email can't be received:

  1. Spam: The e-mail was marked as spam. Often it's not clear what went wrong, as there is no explanation from the sending or receiving server.
  2. Bounces: The sending or receiving server does not accept the email. This means that an email has bounced. This can come through Spam. In this category an email is considered as 'not accepted' and you often receive a statement from the sending or receiving server why the email has not been accepted.


In some cases, emails might be marked as spam by the receiving server.

How does spam work

A server rates each incoming mail with a score, based on a number of variables. These variables are confidential because attackers would abuse this information to make their spam emails go through.

A perfect score is 100, and every "error" will lower the score. If the score is insufficient, the email is marked as spam.

The score of Rentman emails

Emails sent from Rentman have on average a very good score and are usually not marked as spam.

Of course, this score can vary based on the content of your emails. You can test the score of your emails using tools like MailTester.

How to improve your score

If your emails are being marked as spam, there are some actions you can take to improve your score:

  • Maintain a good  HTML-text ratio - Receiving servers lower the score of emails with a "heavy" amount of HTML code as compared to the text. If you use a lot of HTML coding in your emails, consider reducing the coding or adding text.
  • Maintain a good images-text ratio - What previously said about HTML coding applies to images as well (both inside the text and attached).
  • Maintain a good links-text ratio - What previously said about HTML coding and images also applies to links to website pages.
  • Use a "regular" character size - Using a smaller or larger than average character size might lower your score.
  • Keep testing your score using tools like MailTester, and improve your email templates based on the feedback.

Tip: Suggest your clients to add you as a contact in their email server.

Another factor that might affect the score is that your displayed sender address does not match the actual address of the sender. The impact of this factor is smaller than the ones listed above. You can solve this by verifying your sender address at a cost of €340, but we advise trying first to improve your emails.


The server from the sending server (of Rentman) or the receiving server (of the customer) does not accept the email. The reason for this is often mentioned immediately by email or in the message screen in Rentman.

Find the message screen clicking on your username, on the top right corner. If you do not see the messages icon, your user role does not have the correct rights.

Find the cause of a bounce

An email can be sent, in queue, or Delivering failed. These statuses mean the following:

Status Sent
Meaning The receiving server has marked the email as sent
Status In queue
Meaning The sending server hasn't sent the email yet. This is probably because too many emails are being sent by multiple accounts in batches, with a delay to prevent an email being marked as spam. The sending server automatically tries to resend the emails, up until a defined limit. This cannot be cancelled.
Possible action:
  • Waiting is often the best solution, since the email will generally be sent succesfully.
  • Send the email from your own server.
Status Delivering failed
Meaning The email wasn't sent by the sending server, or wasn't accepted by the receiving server.  If you can't figure out the reason why, please contact us. We may be able to determine the cause. Note: Rentman does not manage the receiving server, therefore we may not be able to always determine a cause.
Possible action:
  • View the common causes in the next section of the article, or contact us.
  • Send the email from your own server.

Common causes of a bounce

Wrong email address This is the most common reason. Please check the email address and try again.
Bounced by receiving server due to spam This may be because the address of is marked as a spam address. Please contact us if this is the case. A short-term solution is to send the email from your own server.
Bounced by sending server because address is on a blacklist Our email client keeps a blacklist of email addresses, which were marked because of various reasons. The email address may have been offline for a short period of time in the past, or the inbox was full. Please contact us if this happens, to let us remove this email address from the blacklist.


Was this article helpful?
2 out of 2 found this helpful



Please sign in to leave a comment.