The default stack size of IIS starting with Windows Server 2003 was changed.  Prior to 2003, it was set to 1 MB.  This is also true of the aspnet_wp.exe process that Windows 2000 uses.

In 2003 and later, it is now set to 256 KB.

This can cause a process to run out of stack space if it has something that uses a recursive function.

This is talked about in our Knowledge Base here.

If you want to change this back to the 1 MB that it used to be, you can use editbin to do this.

EDITBIN /STACK:1048576 w3wp.exe

This will change the process.  You can use dumpbin to view the sizes:

stack

This is before making the change.

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