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Email Delivery Delays

ISC continues to receive reports of ongoing email delivery delays. Please remember email delivery is not instantaneous, and delivery times up to five minutes are considered reasonable in Penn's complicated email environment. Factors like inbound and outbound sanitation services, number and size of attachments, message content and format, and the number of recipients can all affect the delivery time of a message.

If you think there is an unreasonable delay in delivering an email message, please consider the following before reporting it to ISC:

  • Please allow at least 5 minutes for the message to appear.
  • If there is an attachment or any unusual content in the body of the message, please increase that wait time to at least 15 minutes.
  • Have the recipient(s) check their Junk folder in case the message has been flagged as spam. Check their mail filters, and other folders the message may have been filtered to.

If you still think there is a delay in delivering your message, please:

  1. Wait for the message to arrive and capture the entire message, including mail headers. Directions on how to submit message samples to ISC are at https://www.isc.upenn.edu/how-to/how-send-email-headers-isc.
  2. Please open a ticket by contacting Client Care online at http://supportcenter.upenn.edu/ or by email at help@isc.upenn.edu, and attach the sample message.

If the message doesn't arrive after 30 minutes, please make note of the From address, To address, approximate time of sending, and the Subject of the expected message. Then open a ticket with Client Care with that information. When reporting mail delays, please be aware that we must have all pertinent information as soon as possible. If we have to escalate the issue to our mail sanitation vendor, we must adhere to their service requirement of reporting such delays within a 5-day window.

 

Best practices for preventing delivery delays:

  • Compose messages in plain text or HTML, not RTF. Formatting messages in RTF adds an invisible attachment (winmail.dat) to outbound messages, increasing the size of the message.
  • If sending an attachment over 10MB, consider uploading the file to a cloud-based storage service like Microsoft OneDrive or Penn+Box, and share a link to the document instead.
  • If sending to many recipients, consider using a mailing list service like PennNet Mailing Lists, or some other method to distribute your message (Teams, a website, etc...).