Sometimes I need to send emails to large numbers of people. Does Exchange Online limit the number of emails I can send?
Yes. Exchange Online limits the number of recipients per message to 500 and sets a daily recipient limit of 10,000 recipients. If you have email sending needs that exceed these limits, we recommend using one of CU Boulder's bulk/mass email communication services.
Are certain attachments types blocked by Office 365?
Outlook and Outlook on the web do not allow you to receive files of certain types (such as .exe files) as attachments, because of their potential for introducing a virus into your computer. By default, Outlook blocks these files.
For a full list of file types, please review Microsoft's blocked attachments page.
How much storage space does my Exchange Online account have?
All Office 365 accounts by default have 50GB of Storage for email and calendar data. Please note: This limit cannot be increased.
Visit the Outlook on the web Check Mailbox Usage tutorial to learn how to check the capacity of your mailbox or use Microsoft's Manage My Mailbox Size page for additional help.
How long do messages stay in the Deleted Items folder?
The deleted items folder retention period is 30 days. After that, messages are automatically removed from the folder. Items that have been automatically removed from the Deleted Items folder are retained for 30 days before being permanently deleted. You can recover items during the retention period using Outlook or OWA. Visit the Recovering Deleted Items tutorial for instructions.
What do I need to know if I use delegates to manage my Calendar?
OIT has created an Exchange Online Calendaring Best Practices guide to provide guidance to Exchange Online calendar users on the practices and email/calendar clients that best avoid calendaring problems. They have been collected from many years of experience with Exchange and from multiple sources.
Microsoft Defender Quarantine
What is Microsoft Defender Quarantine?
Microsoft Defender Quarantine is a feature that is integrated with Outlook to protect users from harmful emails and spam. It automatically holds suspicious emails in quarantine until the user can review them and decide whether to allow them to be delivered to their inbox or to delete them.
By enabling Defender Quarantine on the Outlook client, OIT is empowering end users to release messages they previously would not have seen.
Is Microsoft Defender enabled for my email?
We are currently running a pilot of this service to a limited number of users within OIT. Assuming the pilot is successful, OIT plans to rollout this new service campuswide later in 2023.
What's the difference between the Quarantine and the Junk Email folder?
The junk email folder is only intended for email that is considered “bulk” email (such as surveys or advertisements) while the Quarantine is intended to prevent harmful emails from ever reaching your inbox. Occasionally emails that are not harmful could end up in the Quarantine, but over time Microsoft is working to improve their detection techniques.
How often will I receive an email notification to check my quarantine?
You will receive a notice daily, but you can check your quarantine at any time by visiting https://security.microsoft.com/quarantine.
How often should I check my quarantine?
It's recommended to check your quarantine regularly to ensure that no legitimate emails are being blocked.
How do I preview an email in quarantine?
To preview an email in quarantine, log into https://security.microsoft.com/quarantine, select the email and click on the Preview button.
How do I release an email from quarantine?
To release an email from quarantine, log into https://security.microsoft.com/quarantine, select the email, and click on the "Release" button if it is available. The email will then be delivered to your inbox. If a message is determined to have a high probability of being harmful, it will require OIT administrator intervention before being released to your inbox.
Messages may also be released directly from the Quarantine notification emails.
How do I delete an email from quarantine?
To delete an email from quarantine, log into https://security.microsoft.com/quarantine, select the email and click the Delete button. Messages may also be deleted directly from the Quarantine notification email.
What is the Safe Senders list?
The safe senders list is a feature used in Microsoft Defender Quarantine to ensure that emails from specific senders are not placed in quarantine. This feature can be useful for safelisting emails from known business partners, colleagues, or other important contacts. While the Safe Senders list can help reduce the chances of legitimate emails being quarantined, it doesn't guarantee that all emails from those senders will be safe, so it's still important to review your quarantine regularly and be vigilant against potential phishing or malicious emails.
How do I add a user to my Safe Senders List?
- Log in to your Outlook Web Account, click on the Settings icon in the top right corner of the screen.
- Click on View all Outlook settings
- Click on Mail
- Click on Junk email
From this menu you can search, add, and delete users from your Safe Senders list.
What should I do if I routinely see messages from a verified sender in my Quarantine or if I accidentally block a legitimate email address?
Legitimate messages may appear in the Quarantine if the sender was accidentally placed on your Blocked Senders list.
- To unblock a legitimate sender, log in to your Outlook Web Account, click on the "Settings" icon in the top right corner of the screen
- Click on View all Outlook settings
- Click Mail
- Then click on Junk email.
- From this menu you can search, add, and delete users from your Blocked Senders list. It's also recommended to review your Blocked Senders list regularly to ensure that no legitimate emails are being blocked.
Can I block a specific user or email address from sending me emails?
Yes, you can block a specific user or email address in the Quarantine tab, which will prevent any future emails from that user or address from being delivered to your inbox. You can also right click emails in your inbox and select either “Block then Block Sender or Junk then Block Sender depending on your client.
Who should I contact if I have further questions or concerns about Microsoft Defender Quarantine?
If you have any further questions or concerns about Microsoft Defender Quarantine, please contact the IT Service Center at 303-735-4357 or email@example.com.