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Email Error Library for supported SMTPs

Navigating email errors can be complex, given the myriad factors that can interfere with successful delivery. This guide elucidates common issues encountered using email services such as Mailgun and Gsuite. From domain verification to request limits, this resource offers insights into prevalent errors, their causes, and potential solutions to facilitate smoother digital communications. Note: For more information about why your email was unsuccessful, please click the ⚠️(red triangle) icon to view more details. * * * ## Error list: Note: If you see an “email not sent” warning because the recipient domain is invalid or restricted, Patient Copilot blocks the email before sending. See our article on: Email Blocking for Invalid or Restricted Domains. ### The domain is not allowed to send: The domain is unverified and requires DNS configuration. Log in to your control panel to view the required DNS records. Log in to Mailgun - (https://login.mailgun.com/login/)[https://login.mailgun.com/login/](https://login.mailgun.com/login/) 1. Expand Sending tab 2. Click the last menu item, Domain Settings 3. Make sure you select the correct domain/subdomain for the location on top 4. Click DNS records on the top middle 5. Click Verify DNS settings and see if all 5 DNS records have a green checkmark? Sometimes it might show if they have all green checkmarks but it might not be the case, you will need to click the Verify DNS Settings button again to refresh the record:!(https://assets.patientcopilot.ai/764c3990cfd3362a.png) * * * ## The domain is not allowed to send: Account Terminated. The agency must contact Mailgun support to see why it got terminated.!(https://assets.patientcopilot.ai/54f83e02150c728a.png) * * * ## Too old It is one of Mailgun’s internal errors that you can clear in the Patient Copilot agency settings. But to find out why you are getting that error, you will need to contact Mailgun support to check further.!(https://assets.patientcopilot.ai/3bee83c24757281b.png) * * * ### Mailgun Send verification error. If the sender’s address is missing or illegible, it may never reach its destination, and even if it does, the recipient won’t be able to respond. Similarly, a sender address verification error can occur in email communication if the recipient server fails to locate the sending domain’s necessary MX records (Mail Exchanger records). Here’s how the problem usually manifests itself: 1. 550 Verification failed for bounce+c72392.3559d@yoursendingdomain.com\nUnrouteable address\nSender verify failed 2. The domain of the sender address bounce+c72392.3559d@yoursendingdomain.com does not exist 3. Sender address rejected: User unknown in virtual mailbox table 4. Could not resolve sender domain 5. Your domain has no DNS/MX entries 6. Requested action not taken: mailbox unavailable invalid DNS MX or A/AAAA resource record. Here are some steps you can take to fix this issue based on your current Mailgun sending domain: #### If you’re using a subdomain: Although not required, we highly recommend pointing your MX records for the domain to Mailgun. This helps prevent Sender Verification Errors. Set the MX records for the subdomain to Mailgun values to fix the error. These are: - Value: mxa.mailgun.org, Priority: 10

  • Value: mxb.mailgun.org, Priority: 10 Wait 24-48 hours for the records to propagate fully, and the error should disappear. If you still see the error, try adjusting the domain in the From field of the message to match the sending domain. #### If you’re using a root domain: If your root domain already has your Email Service Provider’s (ESP’s) MX records in place, the best solution is to add a subdomain for your Mailgun sending. The error should be resolved once you’ve added the subdomain and configured Mailgun’s MX records. Please Note: If your root domain doesn’t have or needs MX records pointing to a hosted mailbox provider, you can add the root domain to your Mailgun account, verify the required TXT AND MX records, and send through the root domain. Remember: Only point your MX records for a domain to one source to avoid email misdirection or loss. 3. Alternate Approaches: If the error persists after trying the above steps, consider these alternatives: - Turn off sender address verification (on the server side with your email provider).
  • Create a “catch-all” within the configuration of your email provider. This ensures that Sender Address Verification will pass when the recipient server checks the sender information for incoming emails. Understanding and troubleshooting these kinds of issues can be technical, but following these steps should help you resolve sender verification errors. This Mailgun article has more information. * * * ### Too many requests The error means that too many email requests were sent simultaneously. Please get in touch with Mailgun support to check for an email limit with the Mailgun account. You can clear the error in the agency settings -> Email services tab. * * * ### Temporary System Problem when using Google Workspace “code”:“EENVELOPE”,“response”:“421 4.3.0 Temporary System Problem. Try again later (10). o11-20020a056e02092b00b0031559b0cb61sm1590122ilt.8 - gsmtp”,“responseCode”:421,“command”:“DATA If you send emails in bulk and receive the error above, this might happen when using Gmail SMTP; please inform the user to use LC Email or send in batches with low volume. * * * ## Error Libraries for Various SMTPs The error libraries for supported SMTPs (Mailgun, Gmail, Outlook, Sendgrid) are available in several formats: - On the web here: https://docs.google.com/spreadsheets/d/e/2PACX-1vSTa4RXIdFexBNK2ZyLj-MGgSL5AnzmpIalokFIsPrGg0HnK5w2zrRmNESWcIcOkG3D7nG2Q7wWsBWq/pubhtml
  • In Google Sheets here: https://docs.google.com/spreadsheets/d/1XIl6TyuMamX2vlts1-lzBVXR2ArCFqiJnTeBxz7qBKQ/edit?usp=sharing
  • Or in the tables below. ### Mailgun: | Code | Error Message | Meaning | Solution | Glossary | | --- | --- | --- | --- | --- | | 400 | from parameter is missing | The sender’s email address is not provided | Include the sender’s email in the ‘from’ parameter | ‘from’ parameter: Sender’s email address | | 400 | to parameter is missing | The receiver’s email address is not provided | Include the receiver’s email in the ‘to’ parameter | ‘to’ parameter: Receiver’s email address | | 400 | message parameter is missing | The email body is not provided | Include the email body in the ‘message’ parameter | ‘message’ parameter: Email body | | 400 | ‘message’ parameter is not a file | The ‘message’ parameter is expected to be a file but isn’t | Provide the message as a file | ‘message’ parameter: Email body, in this case expected as a file | | 400 | Need at least one of ‘text’ or ‘html’ parameters specified | Neither plain text nor HTML versions of the email are provided | Include at least one of the ‘text’ or ‘html’ parameters | ‘text’/‘html’ parameters: Plain text/HTML versions of the email | | 400 | Only one parameters ‘html’ or ‘template’ is allowed | Both ‘html’ and ‘template’ parameters are provided, but only one is allowed | Provide either the ‘html’ or ‘template’ parameter, not both | ‘html’/‘template’ parameters: HTML version of the email / Template for the email | | 400 | Send options (parameters starting with o:, h:, or v:) are limited to 16 kB total | The send options provided exceed the 16 kB limit | Reduce the size of send options to less than 16 kB | ‘o:’, ‘h:’, ‘v:’ parameters: Send options for the email | | 400 | Too many recipients; max is 1000 | The email is addressed to more than 1000 recipients | Limit the number of recipients to 1000 or less | Recipients: The individuals or groups receiving the email | | 400 | Header name must be pure ASCII: | The header name contains non-ASCII characters | Use only ASCII characters in the header name | ASCII: American Standard Code for Information Interchange, a character encoding standard | | 400 | is not an RFC-2822 compliant date | The provided date is not compliant with RFC-2822 | Ensure the date is formatted according to RFC-2822 standards | RFC-2822: Internet Message Format specification | | 400 | to parameter is not a valid address. please check documentation | The receiver’s email address is invalid | Check and correct the format of the receiver’s email address | ‘to’ parameter: Receiver’s email address | | 400 | Invalid request content type. Expecting ‘multipart/form-data’ but got ‘application/x-www-form-urlencoded’ | The content type of the request is not what is expected | Change the request content type to ‘multipart/form-data’ | ‘multipart/form-data’: A type of HTTP request commonly used for file uploads | | 400 | malformed multipart/form-data request | The ‘multipart/form-data’ request is formatted incorrectly | Correct the format of the ‘multipart/form-data’ request | ‘multipart/form-data’: A type of HTTP request commonly used for file uploads | | 400 | unable to parse request: invalid URL escape | The URL in the request contains invalid escape characters | Correct the escape characters in the URL | URL escape characters: Characters used in a URL to represent certain other characters | | 400 | unable to parse request: unexpected EOF | The request ends unexpectedly | Check the request for missing information or incorrect formatting | EOF: End of File, in this case referring to the end of the request | | 400 |