Curing ASP-Run Executable Problems in IIS 5.0

We use ServerObjects' AspExec ActiveX control to run an executable from Active Server Pages (ASP). This control has always worked for us under Microsoft Internet Information Server (IIS) 4.0 on Windows NT 4.0. However, the executable isn't working on our Windows 2000 server. The program is running in a hidden window, so we can't troubleshoot the problem. The executable won't terminate the process, and we can't kill it through Task Manager, which displays an Access denied error. The problem isn't specific to our executable. Do you know of another way to run executables from ASP, or can you tell us how to stop the executable or make the program run in a visible window?

Your problem relates to differences between the default application protection and isolation settings in Internet Information Services (IIS) 5.0 and in IIS 4.0. These settings control how applications run on the server. Applications can run in the same process as the Web server (Low setting), in a separate pooled process with other applications (Medium setting), or in an isolated separate process (High setting). You can configure these settings on the Home Directory tab of your IIS system's Web Site Properties dialog box, which Figure 1 shows.

The default setting under IIS 5.0 on Win2K servers is Medium (Pooled). When a site's Application Protection option is set to Medium (Pooled), IIS uses a program called dllhost.exe to execute DLLs, and you end up with an orphaned process. Your program probably requires a setting of Low (IIS Process), which is the default under NT 4.0 and IIS 4.0 and the reason the executable worked under those versions. You should be able to solve the problem by changing the Application Protection option to Low (IIS Process) for all sites on which ASP uses AspExec to call executables. (For more information about the differences between IIS 5.0 and IIS 4.0 and about IIS application settings, see Brett Hill, "Migrating from IIS 4.0 to IIS 5.0," September 2001, and Ken Spencer, "Introducing Internet Information Services 5.0," http://www.win2000mag.com, InstantDoc ID 8212.)