Why does my website sometimes prompt "Service unavailable "?

This is because your website has exceeded the system resource limit or the number of IIS connections (because our VM uses 2003 operating system, when the operating system of 2003 prompts that IIS is too large, the system prompts "too many connections" instead of "service unavailable". If this happens, you can choose to upgrade the host, or check whether someone has leeching. You can often change the directory of the software and images you put. ProgramToo many resources are occupied. For example, for a forum of 100 online users, leiao Forum accounts for more than 10 times of the resources occupied by the Forum. In addition, some endless loop programs, or the program that is not optimized will occupy too much system resources, and the system resources are obviously limited. Because our new virtual host uses the Windows2003 operating system, each website runs in an independent process and does not affect each other.

If a website program occupies too many resources or has too many errors, the system log will prompt: "The application pool 'appolnum' is automatically disabled, the reason is that a series of errors occur in the process that provides services for this application pool, or the prompt is: The application pool '***' exceeds its job restriction settings. For more information, see Help and Support Center in http://go.microsoft.com/fwlink/events.asp.
When you access this website, the message "Service unavailable" is displayed. Generally, the system returns to normal in about 30 seconds, and can be accessed after several refreshes.

If similar errors often occur, optimize your website programs in time or upgrade your VM to a higher model to obtain more system resources.