Changes

One of the roles of an operating system is to determine what to do with the files.
Based on the file extension, the OS decides on a program to use to launch a chosen file. Well, "decides" is inaccurate. Some person told it in advance what to do with it.
Yesterday I got a call about this file to program association being broken with regard to certain image files.
Users couldn't work.
Holy crap.
End of the world.
When I open a picture on my computer, Photoshop starts and displays the image. On these servers, clicking on an image file failed to call any application.
I looked at the file associations and everything looked good.
I even MS Painted a vaguely obscene doodle and clicked it from the desktop.
The proper application opened beautifully.
We ended up examining the network traffic, since the image files the users were needing to view were out on the network.
There was a standard "get" command, followed by a string of text containing no file name (even though one was selected) and correctly expecting an image file.
But there was no response.
A few hours later, we discovered that the server hosting the application itself had been turned off, decommissioned, and replaced by another server.
This would be the end of the story.
Process broke down, communication was never sent, feelings were hurt, and we worked around the difficulty to re-enable functionality to usher in a new era of end-user productivity.
But determining that the application had jumped servers had been so horribly complicated because the documentation for the change was so difficult to find.
And it was difficult to find because the application which was moved was our corporate seamless search application which makes finding documentation possible across our sprawling network.