ASP running on IIS 6.0 500 Error solution)

Recently, ASP developed an invoicing system (Development Environment: Windows2000 + dw mx 2004 + IIS 5.0). It runs and debugs on the local machine normally without any error information, but it will not work if you put it on Windows Server 2003, And the login page can be accessed, but when the file in the lower-level directory is executed, the browser directly jumps out of the following error page:

There is no other valuable information, because the website runs normally on my computer, I guess it should be a problem with IIS configuration (I have heard that IIS security has improved and whether there are any restrictions), but my code is very standard ASP code, no third-party plug-ins have been used. However, after viewing the IIS attributes for a long time, all the related options have been selected, and no response is returned. The above page is still displayed. When the home page is messy, another screen pops up to say "no permission to access the parent path ". It's strange. Why is this error reported? This is the default value on IIS 5.0. Has it been canceled on IIS 6.0? Re-open the IIS attribute item, select "main directory", click the "configuration" button above, and select the "option" tab in the pop-up window. It is not checked, for example:

Hook it up, refresh, OK, and the familiar picture is coming out again.
Ask why this error occurs in my code. Almost every page contains several files in the parent directory, as shown in figure <! -- # Include file = "../Conn. asp" -->. Alas, the hateful IIS 6.0.