How does Microsoft Office 365 filter or block emails based on URL reputation?

Email marketer from Reddit explains that Office 365 uses URL reputation to determine if a message should be quarantined. If a URL is associated with phishing or malware, the email might be automatically moved to the quarantine folder.

Email marketer from SenderScoreBlog explains that maintaining a good sender reputation is crucial. URLs in emails can significantly impact this reputation, and Microsoft 365 uses various reputation services to assess URLs and filter or block emails accordingly.

Email marketer from Email Deliverability Tips shares that it's essential to proactively monitor your URL reputation using tools like Google's Safe Browsing status checker. If your URLs are flagged, take immediate action to resolve the issues and request a review.

Marketer from Email Geeks shares that in their experience, Microsoft is not very responsive or receptive to tickets regarding non-block issues.

Email marketer from StackExchange shares that legitimate URLs can sometimes be flagged incorrectly due to shared hosting environments or temporary reputation dips. This can cause false positives and email delivery issues within Office 365.

Email marketer from EmailMarketingCommunity mentions that Microsoft 365 users can report suspicious URLs within emails. If a URL is frequently reported, Microsoft may add it to their internal blocklists, impacting future deliverability.

Email marketer from EmailDeliverabilityForum notes that if your emails contain links that are flagged as phishing attempts, Microsoft 365 will severely penalize your sender reputation, leading to blocking or filtering of your emails.

Marketer from Email Geeks explains that Microsoft is known to block or filter emails based on low-reputation URLs. They suggest sending test emails with and without the suspected URL to a few test accounts.

Email marketer from EmailSecurityBlog explains that using URL shorteners can sometimes negatively impact URL reputation. Since many shorteners are used for spam or malicious purposes, Office 365 may treat emails with shortened URLs with more suspicion.

Email marketer from MXToolbox suggests using their URL reputation checker to evaluate the reputation of URLs. This can help identify if a URL is flagged by any blocklists or security services that Office 365 might use.

Expert from Word to the Wise explains that Microsoft uses various reputation services and internal signals to determine the safety of URLs. This includes factors like the age of the domain, the content hosted on the URL, and whether the URL is present in phishing or malware databases. URLs that trigger negative signals are likely to be filtered or blocked.

Expert from Spam Resource explains that Microsoft will look to see if links within an email are masked using a shortlink service like bit.ly. These are common methods used by spammers to hide a URL's destination so they are given low reputation scores which impacts deliverability.

Documentation from Microsoft Learn explains that Exchange Online Protection (EOP) analyzes URLs in inbound messages for malicious content. If a URL is deemed suspicious, the message can be blocked or sent to quarantine depending on the configured policies. This includes checking against known blocklists and using heuristic analysis.

Documentation from Microsoft Learn details Safe Links in Defender for Office 365. It describes how Safe Links provides URL scanning and rewriting of inbound email messages. When a user clicks a link, the URL is checked in real-time before the website is accessed. Malicious links are blocked, and users are warned about suspicious sites. This helps prevent phishing and malware attacks using URL reputation.

Documentation from Google Safe Browsing details that Office 365 may integrate with Google's Safe Browsing API to assess the safety of URLs. The Safe Browsing tool lets you check website status and is frequently used by security applications.

Documentation from Microsoft Learn describes how Advanced Delivery helps manage allow and block lists of specific IP addresses or domains. It allows administrators to bypass filtering for known safe senders or domains and also add entries to the tenant allow/block list. It can also block domains and URLs based on reputation.

Documentation from Spamhaus details that Office 365 often uses blocklists like the Spamhaus Block List (SBL) and the Domain Block List (DBL) to filter emails. If a URL is listed on these blocklists due to spam or malicious activity, emails containing those URLs are likely to be blocked by Office 365.