Skip To The Main Content

MacMail FAQ


What is MacMail?


MacMail is the email service replacing UnivMail. It provides users with a email and calendar.

Will my email address change?


No, your standard email address will not change. Continue to

What happens if email is sent explicitly to my UnivMail account?


Emails sent to or may receive an unknown user message or mailbox disabled response. You are reminded to use the standard email address

Will my username change?


No, your usename continues to be your MAC ID. Use your MAC ID and password to logon to MacMail.

How do I archive email no longer essential?


Move such emails to the local folders of email client such as Outlook. Do take time to delete unwanted email messages.

I use Thunderbird, what changes do I need to make?


Thunderbird will not natively access all features available on Exchange. Outlook and the web interface athttps://macmail.mcmaster.cawill provide you with all available features.

What features are available on MacMail?


**Email, Calendar, Tasks, Notes, Data Recovery

How do I set up a signature file in Exchange?


Please see the help section within Outlook client or the Outlook Web Access at

How will this affect my Outlook configuration on my home computer?


Any Outlook client must be configured for MacMail as UnivMail will be decommissioned.

How will this affect my Mobile devices?


First configure your mobile devices for MacMail. Next remove the UnivMail configuration when done.

I am unable to add attachments when using the Chrome with OWA.

  You may need to install Microsoft Silverlight. Please see
I am able to connect to MacMail when on campus but not off campus.   If you experience difficulty connecting to MacMail from off campus, you may need to install and use the McMaster VPN found at

When configuring my Android device with Active Sync, it requires administrator access to remotely control some security features on your device.

  This is information on a Microsoft Exchange feature not utilized by MacMail administration.
What is the size limit of a single message?

  The MacMail solution is restricted to 30MB per message. This means that you can have up to 30MB worth of attached items and text in a single message. This could be three 10MB files or one 30MB file but the total cannot exceed 30MB

Why is there a size limit?   Having a limit larger than 30MB puts the e-mail servers at risk for poor performance, internal network congestion; increased vulnerability (higher risk of denial of service attacks), higher cost impacts and inadequate capacity management.

What is the industry standard?   Major e-mail providers, including Gmail, Hotmail, AOL, Yahoo, have standardized on a 25MB limit.The default for MS Exchange is 10MB, the limit has been set to 30MB for MacMail.

What is the impact to migration?   Univmail messages sizes that are 30MB or less will migrate with no issues.
Messages larger than 30GB will not be migrated but moved to a secure storage location.  End users will be provided with a link and password to the secure storage location so messages and attachments can be retrieved.

What are the alternatives for attachments larger than 30MB?     There are numerous services that could be used to transfer files larger than 30MB more conveniently, efficiently and securely using cloud storage providers such as DropBox, Google Drive, SkyDrive, Box....etc. There are also various internal, private storage services, including  Please check with your local IT service providers for more options.

I sent an email to a UnivMail email address and received an unknown user message.   
Server error: '550 unknown user account'

  Do use the standard email format in your email communication. Remind your contacts to use

Do not use or

I sent an email to a UnivMail email address and received an unknown user message.
  >... Mailbox disabled for this recipient


Do use the standard email format in your email communication. Remind your contacts to use

Do not use or

How do I share information from a meeting I am invited to with others (who are) not invited to that meeting?   If you use Microsoft Windows operating system, it is possible to share information. Open Outlook Calendar and click on the meeting with the information you want to share and drag it to Mail in bottom left corner. Next enter the email addresses of the people to share the information with and send. This is not possible in other email clients.