365 Threat Monitor

Receive real-time alerts when email threats breach your Office 365 security and enter your users’ inboxes!

Delete the threats with just one click using this free app

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Start monitoring your M365 – FREE, forever

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Scan all emails as they reach your Office 365 user mailboxes to detect ransomware, phishing and spam. Receive real-time phone alerts and instantly delete threats with just one click. Get real-time security breach updates and instantly delete threats – for free!

Office 365 is not a security solution and does not give you adequate protection.
That can cost you:


Increase in cyberattacks on Office 365 users in two years


Highest ransomware payoff made to date


Percentage of SMBs falling victim to phishing emails last year


Backed by Hornetsecurity’s years of expertise in combatting cyberattacks, 365 Threat Monitor is a free mobile app that detects any threats that breach your Office 365 security and enter your system. It enables you to instantly delete them with just one click: Prevent any damage and save the day!


Use 365 Threat Monitor for free to receive real-time alerts about gaps in your Office 365 security, and delete ransomware, spam and business email compromise attempts

Combat your fear of cyberattacks slipping though and reaching your users’ Office 365 inboxes! In four quick and easy steps, this free email security mobile app gives you real-time alerts when malware infiltrates your system and allows you to delete it remotely, wherever you are.


One of your users receives a suspicious email in their Office 365 inbox.

Receive a real-time alert

Once 365 Threat Monitor identifies a malicious email, it sends you an alert – direct to your phone.

Spam, malware or ransomware?

365 Threat Monitor lets you know which mailbox is affected and by what type of threat.

Delete the malware with 1 click

Delete the threat from the mailbox with just one click on your phone.

What free email security functionality does 365 Threat Monitor provide?

Real-time malware detection and alerting

365 Threat Monitor detects and alerts you about all kinds of suspicious and malicious emails that have made it through your M365 defenses and reached your users’ inboxes, including:

  • Malware such as: Ransomware, viruses, spyware
  • Phishing
  • Spoofed sender identities and content
  • Targeted attacks on:
    • data that requires special protection, such as credit card data, invoices, money orders, etc.
    • at-risk roles, such as accounting, CFO, CEO, HR, etc.
  • Spam and unwanted advertisements
  • And more!
Protection you can count on

To provide you with utmost reliability, 365 Threat Monitor combines Hornetsecurity’s powerful, proprietary technologies to plug your security gaps. These include Email Live Tracking, Threat Defense and Forensic Analyses. They detect attacks through real-time scanning for harmful content, heuristic filtering, and authenticity and integrity verification.

Instant deletion of malicious emails

Using the app’s unique Malware Ex-Post Deletion functionality, you can delete malicious emails from a mailbox immediately after detection. 365 Threat Monitor allows you to make a limited number of deletions.

Threat statistics and reporting

365 Threat Monitor presents you with extensive information and statistics on your current email security status. You can view security reports on the app and get a graphic overview of the threats faced by your M365 organization. You can also adjust the display – choose between an overview of past hours, days or weeks.

Fast and easy setup

365 Threat Monitor is fast and easy to set up: Simply follow these steps and get instant notifications about incoming threats that penetrate your users’ inboxes. 365 Threat Monitor doesn’t impact email performance, and you don’t even need to change your MX records.

Threat Monitor onboarding

Free, forever: You get all this high-performance Office 365 email security without paying us a penny – available both for iOS and Android!

Act today to beef up your Office 365 mailbox security:

About Hornetsecurity

Hornetsecurity is a leading email cloud security and backup provider, protecting the IT infrastructure, digital communication and data of companies and organizations of all sizes. We provide our superior security services globally via 11 redundant, secure data centers.

Powered by our inhouse Security Labs, our award-winning product portfolio covers all key areas of email security, including spam and virus filters, legally compliant archiving and encryption, as well as defense against CEO fraud and ransomware.

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Hornetsecurity Client Konica Minolta
Hornetsecurity Client Gerry Weber
Hornetsecurity Client Claas


think that Office 365 is safe enough.
365 Threat Monitor will quickly show you this isn’t true.


think that additional protection costs too much. 365 Threat Monitor is free, forever.


want additional protection but haven’t given this priority. Act now: Don’t risk it!

Get instant notifications about threats to your business directly to your phone, with the 365 Threat Monitor app for iOS and Android.

Want to take your M365 email security even further?

365 Threat Monitor is part of a suite of robust solutions that cover all your email security needs.  It enables you to experience the benefits of superior security technology without paying a dime and provides exactly what you need to protect your business.

To power up your security, try 365 Total Protection, which automatically blocks threats before they reach user mailboxes. This award-winning solution provides high-performance, wider-ranging, AI-based protection for Office 365, and its automation saves you from having to keep a constant eye on your users’ mailboxes.

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While 365 Threat Monitor can only alert you to email threats as they enter your users’ inboxes, upgrading to 365 Total Protection Enterprise will give you compete security.
Features 365 Total Protection Enterprise 365 Threat Monitor
Block threats BEFORE they reach end user mailboxes
Email deletion via the 365 Threat Monitor app after delivery to end user mailboxes Not needed (see above) Limited number of
manual deletions
Outlook allow and deny lists
Email attachment content control
Easy-to-use centralized email encryption with S/MIME and TLS
Compliance filter rule engine
Attachment content control
Email archiving / 10-year email retention / eDiscovery
Easy-to-use user-based individual signatures and company disclaimers

Don’t risk it. It’s easy to play it safe – with Hornetsecurity.

365 Threat Monitor helps you to keep your users’ Office 365 inboxes clean – in the easiest possible way! Delete threats directly with your phone – FOR FREE, forever.

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