SonicWall's licensing server disabled subscription-based security services for thousands of customers for several hours.

SonicWall products contacting a particular SonicWall licensing server began receiving erroneous responses and shutting down. Customers received an email because the monitoring systems indicated that their SonicWall product might have been affected.

"This may have caused the product license key to be reset, and in some cases may have affected the products' operation. The issue has been corrected and all servers and licensing functions have been restored," says SonicWall.

Since the products listed included SonicWall UTM Firewall Appliances-PRO series, TZ series and NSA series; all SonicWall Email Security Appliances and Email Security software; SonicWall Content Security Manager Appliances; all Continuous Data Protection Appliances; and SGMS managed appliances, it would have left many companies completely vulnerable for three hours.

However, customers are furious that so much of their company security seemed to be dependent on a server that was spending all its time working out whether or not their licenses were valid.