Managing Undeliverable Notices

As part of the Polaris notification process, Polaris will send notices to patrons via email, text or phone.  When an email or text message is sent but cannot be successfully delivered to a patron, it will be considered "undeliverable" and "bounce back" to the library that sent it.  

There are several reasons why an email/text notice might be bounce, including:

• A typo or misspelling in the patron's email address
• The patron's email account no longer exists
• The patron's email account is full or temporarily unavailable
• The text message carrier is incorrect 

Sometimes, the patron's email provider may also temporarily block or throttle incoming email for security or spam purposes.  When this occurs, messages may be delayed in their delivery or denied altogether

When a notification fails, a message will be sent to the library's email address that sends patron notifications. This account can vary by library but is usually a generic email like "noreply@library" or "circ@library."  The message will typically include the address that the message was intended for and an explanation of why it failed:  For example:

• The email account that you tried to reach does not exist. Please try double-checking the recipient's email address for typos or unnecessary spaces.   
• Sorry, your message to example@yahoo.com cannot be delivered. This mailbox is disabled
• Error: Invalid user address.  Error message below: 550 - Requested action not taken: no such user here.  

To maintain the reputation to email server, libraries should routinely monitor failed notices.  If left unattended, Polaris will continue to send messages that will repeatedly fail. Repeated failures will damage the email sender's reputation which could prevent future messages from going out successfully.

Processing Undeliverable Emails

Libraries should plan to regularly monitor undeliverable messages. This should be done at least weekly, but daily is recommended. 

To check for undeliverable emails, open the library's notices inbox. For each undeliverable message determine the type of message (email/text) and why it failed.

• Emails that are incorrect or no longer exist - If the message indicates that the patron's email address does not exist
  • Open the patron's account in Polaris/Leap
  • Remove the email address from the patron's account.
  • Add a Non-Blocking Note with the email address, the date, and your name indicating that the email bounced back as undeliverable.
  • Change the patron's notification preference to phone or text messaging
  • (Optionally): Contact the patron to verify the correct email address.
• Emails that are full or temporarily unavailable - If the message indicates that the patron's email address exists, but they currently cannot receive email.
  • The patron may receive the notice when the mailbox becomes available again. However, if notices continue to bounce on subsequent days, follow the steps above to change the patron's notification preference.
• Text Messages that indicate the user does not exist - If the message indicates that the text message could not be sent because the user does not exist
  • Open the patron's account in Polaris/Leap.
  • Verify the patron's cell phone carrier using FreeCarrierLookup. 
  • If the tool suggests a different provider, change the patron's carrier.  
    • If the provider is correct, change the patron's notification preference to email or phone and remove the option for "Additional TXT notices"
    • Add a Non-Blocking Note to the patron's account with the date and your name indicating that a text message bounced back as undeliverable.  
• Text Messages that indicate the message sender has been rejected - If the message indicates that the phone number exists, but the mobile carrier has rejected the notice.
  • The patron may receive the message once the carrier lifts the block.  However, if text messages continue to bounce on subsequent days, follow the steps above to change the patron's notification preference.