The server application is unavailable, and the Web application that attempts to access this web server is currently unavailable

The server application is unavailable.
The Web application you are attempting to access on this web server is currently unavailable. Please click "refresh" in the web browser to try your request again.

Administrator Note: you can find the error details for the specific request failure cause in the system event log of the Web server. Check this log item to find out the cause of this error.

This is the case. My machine is equipped with. netframework1.1 and 2.0. First, this error occurs in the 2.0 program I opened. After this error is found, the program I typed 1.1 cannot run. I chose the most traditional method to restart my system. The problem still remains unchanged, so I had to reinstall IIS and configure both the 1.1 and 2.0 frameworks. The result is that the 2.0 program can run, and the 1.1 program is still the error.

There is no way to go online and check if there is any relevant information. I saw this article:

Http://www.cnblogs.com/cowbird/archive/2005/02/16/104546.html

But I thought the problem was not like that. I thought about it and thought about viewing application logs:

Change the application pool of the next virtual directory. Use different application pools for the virtual directories of ASP. NET 1.1 and ASP. NET 2.0.

Solve the problem. All right!

The upstairs is a master, and it is indeed an application pool problem. The new pool problem is solved for the ASP. net2.0 site.
To create an application pool
1. Click Start, point to program, and click Control Panel ".
2. Double-click "Administrative Tools" and double-click "Internet Information Service (IIS )".
3. Right-click application pool, point to new, and click application pool ".
4. Type apppool1 in the application pool ID text box.
5. Click OK ".

Allocate applications to the application pool
1. Click Start, point to program, and click Control Panel ".
2. Double-click "Administrative Tools" and double-click "Internet Information Service (IIS )".
3. Double-click "web site ".
4. Double-click "Default web site ".
5. Right-click debugapp1 and click Properties ".
6. In the "main directory" tab, select "apppool1" in the "application pool" list box, and click "OK ".

The most important thing is to set the application pool --> properties --> identifier --> predefine the account as the local system.
 
After reading n methods, I did not use them any more. I personally used this method. Especially, the last step is the most important. Remember!