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1508

What is "rate limiting"?

When you're sending email via the Exchange servers (including Outlook Web App) or if you are sending from a machine off campus, we limit the number of emails you can send to external recipients (that is, addresses not ending with sussex.ac.uk).

We use rate-limiting as a precaution against spamming. If your account has been compromised (for example if you have been tricked into giving away your username and password in response to a phishing email), your email account might be used to send high volumes of spam. In the worst cases this leads to repercussions for the University, so to limit the damage that can be done, we prevent large numbers of emails being sent from a single account. 

All email sent via the Exchange servers (including OWA) or from a machine off campus will be limited to a certain number of emails per day (but still plenty enough for you to do normal emailing).

If you need to send greater volumes of email, then please consider these options:

• Use the Sussex mailing list service if your email concerns University business, research or academic work
  
• Use Jisc's mailing list service if your list is academic, but not specific to Sussex
  
• Use an external, private email account if your emails are not related to University business
  
• Contact IT services for alternative solutions if the options above don't meet your needs

In calculating the daily limit, the mail system counts every address in your recipient list, whether the address is that of an individual or that of a mailing list.  A mailing list is counted as a single address, irrespective of the number of member addresses it contains.