If you are hosting a site with Microsoft Internet Information Services (IIS) 7.0, you should be aware of a potential bug that could take your site offline.
IIS may not always get along with your antivirus updates. DHIT recently encountered an issue in which a McAfee antivirus update causes a key DLL to stop loading and IIS Application Pool to stop, which consequently disables website hosting. When attempting to load an IIS-administered site, you will see a 503 error (Service Unavailable):
The particular issue may arise if a component of your antivirus software is removed or expired. For example, your McAfee Host Intrusion Prevention client could be inadvertently updated without all necessary components, uninstalled or otherwise corrupted.
The fix for this issue is quick (and relatively painless), involving a few edits to the applicationHost configuration file.
There are other, related IIS issues detailed in Microsoft support documentation here.
While the fix for this bug straightforward, catching these issues in a timely manner may not be. DHIT uses Microsoft Internet Information Services in a variety of implementations for our applications and has experience ensuring hosting stability.
We recommend not only staying current on Windows and antivirus software updates, but also maintaining a level of support to ensure that potential issues are monitored and remedied quickly to minimize downtime and vulnerability.
DHIT offers tiers of support to accommodate not only ongoing software customization but server continuity. Please contact us with any questions about this issue and keep your health data environment running smoothly.