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Cornell email attachment size is being lowered

This message is about a change to Cornell’s Exchange email and calendar system that will be made on July 14-15.

The weekend of July 14 and 15, CIT will be lowering the limit on email message sizes to 25 MB (megabytes). We will also be upgrading the Exchange 2010 email and calendar system to Service Pack 2. The upgrade resolves several client email problems, especially with Outlook 2011, and is required for the campus migration to Microsoft’s Office 365 service, which will begin in the fall semester.

About the new 25-MB message size limit
 Starting Saturday, July 14, a new message size limit will prevent you from sending or receiving any message that is larger than 25 MB using Cornell’s Exchange email and calendar system. You will see an error message if your message is too big.
Why is this change needed?
The new message size limit of 25 MB is required for Office 365. An very low percentage of email sent by Cornell users is over the new 25-MB limit (the current limit is 50 MB).
What if I need to share a file that is larger than 25 MB?
Starting July 14, you’ll need to choose a method besides email to send files that exceed 25 MB. Your department may give you specific guidance or requirements. In addition, all Cornell faculty, staff, and students have the option to use Cornell’s new Box service, or Cornell DropBox, to share files within the university and with non-Cornell colleagues.
Cornell Box (
— accepts files up to 2 GB in size (total storage space is 10 GB)
— can store files indefinitely
— includes collaboration and sharing options and document versions

Cornell DropBox (
— accepts files up to 2 GB in size
— can be used for confidential data
— can store files for up to 21 days
What about messages I already sent or received that were larger than 25 MB?
The change on July 14 will have no effect on messages you already sent or received. If you are thinking ahead to the Office 365 campus migration that will start in the fall semester and wondering what will happen then, Microsoft and CIT are working on plans for finding and storing messages that are larger than 25 MB. Once those plans are finalized, you’ll be hearing more. In the meantime, those messages will continue to be available in your mailbox.
Questions about Cornell Box, Cornell DropBox, or the message size limit: 607 255-5500
Questions about Office 365: or

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