UPDATE 1: Exchange 2003 E-mail Delivery Delays/Rejections – January 14, 2010 11:30am onwards

Exchange customers may have noticed some e-mails being rejected over the last 24 hours, particularly when sending to Hotmail accounts. Yesterday, UBC Exchange support staff discovered that two compromised Exchange e-mail accounts were being used to send out large amounts of spam. As a result, Hotmail, WPCG and all other e-mail providers that use a particular spam blocking software (Spamcop) began blocking e-mail originating from our Exchange servers. We have addressed the issue of the compromised accounts, and have been working with various e-mail providers to remove our servers from their block lists. WPCG has already removed their blocks, and Hotmail has agreed to remove theirs, but we are waiting for confirmation that this has been done.
If you send an e-mail and it is rejected, you should rule out this issue before assuming it is an invalid address. You can check the service bulletins website to confirm whether this problem has been resolved at https://bulletins.it.ubc.ca – click on the Exchange e-mail category for easy access.
Please note that we are experiencing a higher volume of malicious attacks, mostly through e-mail. Please be vigilant about keeping anti-virus software up to date, and do not respond to e-mails asking you to respond with your login and password, or click on links to other websites. UBC IT staff will never ask you to provide them with your login and password.
If you believe your account may have been compromised, please contact security@ubc.ca and your departmental administrator immediately.