From AutoIt website
Using AutoIt, it is possible to handle the tasks that Selenium can't do. It is possible to upload/download files using AutoIt in Selenium.
Here are the ways to find a window,
Advanced Window Descriptions
A special description can be used as the window title parameter. This description can be used to identify a window by the following properties:
TITLE - Window title
CLASS - The internal window classname
REGEXPTITLE - Window title using a regular expression (if the regular expression is wrong @error will be set to 2)
REGEXPCLASS - Window classname using a regular expression (if the regular expression is wrong @error will be set to 2)
LAST - Last window used in a previous AutoIt command
ACTIVE - Currently active window
X \ Y \ W \ H - The position and size of a window
INSTANCE - The 1-based instance when all given properties match
Check the below docs,
Window Titles and Text (Advanced)
Now, How to use this Selenium?
1. Install AutoIt and write a simple script. AutoIt bundles the ScitTE editor for this. Code Editors such as Notepad++ supports AutoIt syntax.
2. Compile that script into an EXE or make a batch file to run that script.
3. Call that EXE/Batch file from your code.
I've encountered an issue when trying to run AutoIt script. It throws an DLL alert before executing the script. Installing AutoIt, solved that one. So, you may need to install the machines you want to run.