IIS HTTP Error 500.19, Error Code 0x8007000d

I probably come across this error at least once per year. Ran into it again today when setting up a website to host locally in IIS, on a computer I don’t use much.

HTTP Error 500.19 - Internal Server Error
The requested page cannot be accessed because the related configuration data for the page is invalid.

Detailed Error Information:
Module    IIS Web Core
Notification    Unknown
Handler    Not yet determined
Error Code    0x8007000d

Config Source:
   -1:
    0:


Microsoft’s documentation for that error code helpfully points out:

"This problem occurs because the ApplicationHost.config file or the Web.config file contains a malformed XML element.“

Well that clears it up. Just remove the malformed XML element on line 0…

Except that the site runs just fine on other systems, and even in IIS Express on the same machine that’s causing the error, so clearly there’s no “malformed XML”.  Anyway, it turns out that if your web.config has a section for something like IIS’ URL Rewrite module, but you don’t have it installed, IIS will get so mad that all you’ll deserve is the silent scorn of an empty error message.

In my case, the solution was to install the URL Rewrite module via the web platform installer.