There are a number of known limitations with certain Microsft Office 365 applications . Below are some of the most freqently queried limitations worth keeping in mind when using Office 365 Apps. Please note that as Microsoft develops its Office 365 Applications these limitations are subject to change. 

If there are other limitations that you are aware of but are not listed here, then please contact the ServiceDesk and let us know. We would be glad to hear from you. 

Mail Limitations

Single Sign On Will Not Work For Outlook

Single-Sign On ensures that you do not need to re-enter your credentials each time you start Outlook as you have already entered your credentials when logging on to your PC. The simple workaround is to ensure that you tick the "Remember my credentials" checkbox when you start Outlook. Please note your username is in the form

Rate Limits

Exhange online is a cloud-based email filtering service that helps protect NUI Galway, and ultimately your mailbox, against spam and malware. It includes features to safeguard against messaging-policy violations.

In Exchange Online limits are applied to messages, senders, or recipients to combat spam and mass-mailing worms or viruses. Recipient and sender limits are outlined in the table below.

FeatureOffice 365 Education
Recipient Rate Limit 10,000 receipient per 24 hour period, of which less than 1500 can be sent externally
Recipient Limit 500 recipients 
Message Rate Limit
(SMTP Client Submissions Only)
30 messages per minute

Limits on Distribution Groups can be found below. The maximum number of members in a Distribution Group is 100,000 and those that contain more than 5,000 members must have delivery management or message approval options configured.

Delivery management specifies a list of senders who are allowed to send messages to the distribution group. Message approval specifies one or more moderators who must approve all messages sent to the distribution group.

FeatureOffice 365 Education
Maximum Number of Distribution Group Members 100,000 Members
Limit Sending Messages to Large Distribution Group 5,000 or More Members
Maximum Message Size for Large Distribution Group 2MB

For distribution groups stored in an organisation's address book, the group is counted as one recipient. For distribution groups stored in the Contacts folder of a mailbox, the members of the group are counted individually.

All limits can be found on the Microsoft WebsiteNote: These are Microsoft’s standards and are subject to change based on Microsoft best practice.

Note: The NUI Galway Marketing and Communications Office have procuded mass email products. If you need to send a mass email from NUI Galway, it may be advisable to contact the Marketing and Communications Office for more information.

Recalling a Message via Outlook Web App (OWA)

Recall option is not available on OWA. The option is available with the Outlook program of Office package only.

OneDrive Limitations

Shared Document Visability

Be aware that if an NUI Galway staff member opts to share a OneDrive document with everyone then NUI Galway students also have visibility of the document.

OneDrive Item Limit

You can sync up to 20,000 items in your OneDrive library, including folders and files.

Max File Size

The maximum size of a file that can be synced to OneDrive is 2 GB.

Illegal Characters

The following characters in the file name will cause a problem in SharePoint Online (OneDrive):

 \ / : * ? " < > | # %

Additionally, if a filename begins with a period (.), underscore (_) or a tilde (~), you will encounter sync issues

Sharing Large Files

Sharing Large Files

Click Here and Learn How to Sharing Large Files Amongst Your Colleagues Using FileSender