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  • Writer's pictureRachel Hanlon

Update on Hook Security issue

Updated: Feb 16, 2023

Please see below update on the ongoing issue with Hook Security email deliverability:

Due to recent updates with Microsoft Defender SmartScreen, it has come to our attention that Hook emails are flagged as malicious, and therefore, are quarantined for our Microsoft Outlook customers. This does not affect Google Workspace users.

We are working closely with Hook Security to immediately address this inconvenience. Our team is also working to identify work around for our clients until this this system error with Microsoft is resolved.

There are two things we advise for Microsoft customers in the meantime:

1. Please report the testingcenter[dot]net and hooksecurity[dot]co to Microsoft for reclassification. This can be found by navigating to security[dot]microsoft[dot]com as an admin and clicking the submissions tab under "Actions and Submissions".

2. Add testingcenter[dot]net and hooksecurity[dot]co to the safe sender list

At present, the above recommendations have resulted in restoration of service for VISO, however, as Microsoft’s AI keep flagging the Hook domain as malicious we are unsure if this will be a permanent fix as yet. Will we continue to monitor and update accordingly.

We will continue to communicate with Hook Security daily on this issue and we will be sending out a daily update until we are confident this issue is resolved.

We sincerely apologies for this inconvenience.

Update 13/02/23:

We continue to remain vigilant and persistent with Hook Security to ensure that Microsoft's "advanced" tools will no longer target their commercial domain. We will intend to continue to provide updates daily until this matter is resolved.

In the meantime, please make note of the new Portal and School domains: portal [dot] hooksecurity [dot] net school [dot] hooksecurity [dot] net

Update 14/02/23:

As of yesterday (13th) evening, Hook Security were informed by Microsoft engineers that they have applied the band-aid of safelisting/whitelisting their domain in Microsoft's system. Hook still need to take steps to properly delist their domain, but there is solution to help us get back to business as usual.

That said, Hook Security's old application domain (testingcenter[dot]net) will be deprecated and no longer available to our clients. New domains and are up and fully functioning except for our partner and clients who have chosen to whitelabel the school domain.

Until further notice, any school domain whitelabeling will revert back to testingcenter[dot]net and will not work. Hook are currently working on a solution for the domain whitelabeling issue, and we do not currently have an ETA for its return to functionality.

Update 16/02/23

We thank you for your patience as we pull together an update on Hooks domain blocking and quarantine issues with Microsoft Office clients.

Hook Security have spent the last 48 hours testing, and we believe Microsoft has successfully "whitelisted" their domain in their system. (As of note, they no longer permanently "delist" any domains per their Zero Trust compliance policies.)

The issue has now been resolved, by whitelisting the domain all users will now receive their security awareness training.

All IP addresses will remain the same.

Thank you again for your patience during this time!

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