Event ID 5002 and 5011: the WsusPool application pool keeps dying
Event ID 5002, 5011 and 5013 mean WsusPool crashed enough times to be disabled. Raise memory limits and prune the SUSDB to keep the pool alive.
HTTP 500.19 on Exchange virtual directories: broken IIS configuration files
HTTP 500.19 means IIS cannot read the web.config for an Exchange virtual directory. Learn how to reset the vdir and revive its application pool.