This is a simple test to see if your browser is automatically mangling your URLs. The following links will either take you to the correctly specified page ("Good!") or another incorrect URL it fabricated ("Bad!"). There are no links here to the "bad" page, so if you are taken there your browser did something wrong.
Note, the manual and automatic tests maye give different results if
the browser mangles http-equiv="refresh"
URLs differently
than normal links (the case with Opera).
If you got the "bad" page, your browser is silently modifying the URL to accommodate the arbitrary limitations of Windows. Specifically, it's incorrectly changing backslashes (\) to slashes (/).
This link must take you to the right page, otherwise your browser is completely broken. If you went to the wrong page here then it is impossible to point your browser to the right page. I am not aware of any browsers that fail this test.