503 service unavailable due to “The Module DLL …compdyn.dll failed to load”

Quickly helping  one of colleague where after restoring applicationhost.config from the back up on win2k8 IIS 7 we started receiving 503 Service Unavailable on the browser. As the very first step was to check event viewer where we had the following logged: Log Name:      Application Source:        Microsoft-Windows-IIS-W3SVC-WP Date:          7/28/2009 12:46:10 AM Event ID:      2280 Task…

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