On April 16, 2025, Zoom, the widely utilized video conferencing platform, experienced a significant global outage that rendered its services inaccessible to millions of users for nearly two hours. This disruption, occurring between 11:25 AM and 1:12 PM Pacific Daylight Time (PDT), was traced back to a miscommunication between Zoom’s domain registrar, Markmonitor, and the domain registry provider, GoDaddy. This miscommunication led to an unintended server block on the zoom.us domain, effectively disconnecting Zoom’s services from the internet.
Incident Overview
The outage had a profound impact on users worldwide, particularly in the United States and various other countries. Individuals attempting to access Zoom’s services, including meetings, webinars, and the company’s own website, encountered error messages such as This site can’t be reached and Check if there’s a typo in zoom.us. Those already engaged in ongoing meetings were largely unaffected; however, initiating or joining new sessions became impossible during the outage period.
According to Downdetector.com, a platform that monitors service disruptions, reports of the outage peaked at 67,280 users at 3:01 PM Eastern Time (ET). The widespread nature of the issue underscored the critical role Zoom plays in daily communications for businesses, educational institutions, and individuals globally.
Root Cause Analysis
Zoom’s internal investigation revealed that while its domain name servers were operational, DNS resolution for the zoom.us domain was failing at the top-level domain (TLD) level. The TLD nameservers lacked the necessary records for zoom.us, rendering the domain inaccessible. This issue was traced back to a server block imposed by GoDaddy Registry, the manager of the .us TLD, following a miscommunication with Markmonitor, Zoom’s domain management provider.
The miscommunication led GoDaddy to mistakenly place a server block on the zoom.us domain, effectively removing it from the internet’s address system. Notably, there was no evidence of a product malfunction, security breach, network failure, or Distributed Denial of Service (DDoS) attack during this incident.
Resolution Efforts
Upon identifying the root cause, Zoom collaborated closely with Markmonitor and GoDaddy to remove the server block and restore DNS records. However, due to the nature of DNS caching across the internet, it took additional time for the corrections to propagate fully. To expedite the restoration process, Zoom provided instructions for users on Windows and Mac systems to flush their DNS cache, a procedure that requires some technical knowledge.
By 1:55 PM PDT, the majority of Zoom’s services were restored, and the company confirmed full resolution later that afternoon. In a public statement, Zoom apologized for the disruption, acknowledging the critical nature of their services and their commitment to maintaining high availability.
Preventive Measures and Industry Implications
In response to the incident, a registry lock was placed on the zoom.us domain. This measure restricts server block commands and adds an additional layer of manual confirmation for any future changes, thereby enhancing the domain’s security and stability. Both GoDaddy and Markmonitor are reviewing their processes to ensure more robust communication and to prevent similar issues in the future.
The outage serves as a stark reminder of the vulnerabilities inherent in digital service infrastructures. As businesses and individuals increasingly rely on cloud-based collaboration tools, the resilience of these services is only as strong as the weakest link in their supply chain. This incident underscores the necessity for heightened vigilance, redundancy, and robust communication protocols in domain management and other critical service components.
Broader Context and Comparisons
This event is not isolated in the realm of digital service disruptions. For instance, in August 2024, cybersecurity firm CrowdStrike faced a class-action lawsuit due to a faulty software update that caused the crash of millions of Windows devices globally, leading to significant disruptions across various industries. The incident was considered one of the largest IT outages in history, affecting sectors such as aviation and banking.
Similarly, in August 2020, Zoom experienced a partial global outage that affected users primarily on the East Coast of the United States and parts of Europe. The company apologized for the disruption and worked swiftly to resolve the issue, highlighting the challenges of maintaining uninterrupted service amid surging demand during the COVID-19 pandemic.
These incidents highlight the critical importance of robust infrastructure, effective communication, and proactive measures in preventing and mitigating service disruptions. They also emphasize the need for organizations to have contingency plans and alternative communication channels to ensure continuity in the face of unexpected outages.
Conclusion
The April 16, 2025, Zoom outage, caused by a miscommunication leading to a server block on the zoom.us domain, disrupted millions of users worldwide and highlighted the intricate dependencies within digital service infrastructures. The swift resolution and subsequent preventive measures taken by Zoom, Markmonitor, and GoDaddy demonstrate a commitment to maintaining service reliability. However, this incident serves as a crucial reminder of the need for continuous vigilance, robust communication protocols, and comprehensive contingency planning in the ever-evolving digital landscape.
