Updated Fixing Errors Automatically (markdown)

Author: gsherwood

wiki/Fixing-Errors-Automatically.md

@@ -43,6 +43,8 @@ Diff reports are more easily used when output to a file. They can then be applie
     $ patch -p0 -ui /path/to/changes.diff
     patching file /path/to/code/file.php
 
+> Note: The `*nix` `diff` command is required for generating reports in `diff` format. Windows users may need to ensure that the `diff` command is available by either installing [DiffUtils](http://gnuwin32.sourceforge.net/packages/diffutils.htm) or, if available, adding the Git `/usr/bin/` subdirectory to the Windows system `PATH`.
+
 ## Using the PHP Code Beautifier and Fixer
 To automatically fix as many sniff violations as possible, use the `phpcbf` command in place of the `phpcs` command. While most of the PHPCS command line arguments can be used by PHPCBF, some are specific to reporting and will be ignored. Running PHPCBF with the `-h` or `--help` command line arguments will print a list of commands that PHPCBF will respond to. The output of `phpcbf -h` is shown below.
 ```