LockHunter - It is a free tool to delete files blocked by something you do not know.
Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
FileASSASSIN - FileASSASSIN is an application that can delete any type of locked files that are on your computer.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
IObit Unlocker - Never Worry about “Cannot Delete Files” on Your PC
Better Uptime - We call you when your website goes down