Trouble Shooting Email Delivery - Avoiding Being "Blacklisted"

It is crucial for organizations relying on email for critical operations to ensure that their email list is up-to-date and free of errors. The governing bodies regulating email traffic on the internet have become increasingly strict in their enforcement of sending emails to invalid or incorrect email addresses. Thus, caution must be exercised to avoid any negative consequences.

Spam Monitoring Organizations use "Spamtraps" to detect and monitor those Organizations that send these invalid or incorrect emails.

An email account that repeatedly sends emails to invalid/incorrect addressees will be identified by these Spamtraps, and the email account will be placed on a "Blacklist".

Being placed on a "Blacklist" can cause your organization to be unable to deliver emails.

The following are troubleshooting suggestions to help keep your email list accurate and to troubleshoot issues if you are blacklisted.


Maintain a clean and verified email list for your Contacts.

In order to improve email delivery, it is imperative that you ensure your active contacts have verified their email addresses. Delivery of emails to unverified emails will dramatically increase the likelihood that your organization will be blacklisted and violates the "Best Practices" of most Spam Monitoring Organizations.

Review a list of Contacts based on the email status (Verified/Unverified) using the following steps:

  1. In DrugPak, go to the Companies Page.
  2. Click on the Contacts tab to view the list of all Contacts in DrugPak.
  3. Create the following Filter:
     Filter Field = VerifyPending
     Match When = Equals
     Match On = Yes

Troubleshooting hints:
If the contact claims non-receipt of the verification email, please check the spelling of the email address and try again.

Ask your contacts to place the following domain on their spam filter "White List" or "Approved Senders" list:
Some systems allow for whitelisting IP addresses.  ScreenHubb outgoing emails are sent from and


View a list of failed and rejected email sent from your account through the email tab of the ScreenHubb Dashboard.

  1. Login to Screenubb.
  2. From the Dashboard click on the "Email" tab.
  3. Scroll to the bottom of the page to the "Failed" email list.

Error Message(s) examples that indicate your organization is on a "Blacklist":

Unable to connect to server: Connection refused. [IP-XX.XX.XX.XXX] your IP is in (Name of Spam Monitoring Organization) RBL.
Unable to connect to server: Your access to this mail system has been rejected due to the sending MTA's poor reputation. If you believe that this failure is in error, please contact the intended recipient via alternate means.
Unable to connect to  server: (Internet Service Provider Server) your IP was found on one or more DNSBLs.

Unable to connect to server: (Email Server); Client host [XX.XX.XX.XXX] blocked using (Name of Spam Monitoring Organization) SBL.

Trouble Shooting Actions

Ensure the email has been verified

If the email has not been verified, reach out to the Contact and verify their email is correct, make necessary corrections, resend the verification email, and ensure Contact completes the verification.

If the email has been verified, reach out to the Contact and have them place the following domain on their "White List" or "Accepted Senders" list:

Have your Contacts check their "Spam" or "Junk Email" folders in their email clients. If the email is located in the Spam/Junk Email folder, request that they mark the email as not-spam and save that setting.

Once the above steps have been completed, attempt to resend the report or notification.