A File Comparison Tool That's Really Easy To Use [1]

A couple of days ago, one of my web sites stopped working.  Where once were lovely pages of information, there was now nothing but a blank screen.  After investigating the server for a while, I tracked down the problem to a particular config file.  If I changed the config file back to the previous version (of which I luckily had a backup), the site worked just fine.  Put back the current version, and it stopped working again.  I was thus pretty confident that the problem was somewhere within the config file, but now I needed a good tool to let me compare the 2 files in order to spot any differences.

For as long as Windows has been around, it's included a file comparison program called fc.  Run it from a command line, specify 2 files (such things really only work with text files rather than documents), and it will list the differences.  However, the report it produces isn't really of much use.  But thankfully there are some much better ones out there if you look.

I finally settled on a wonderful program called Exam Diff.  As the name suggests, it's designed to let you examine the differences between 2 files.  Start by supplying the 2 filenames, and the results are as shown in the screen shot below.  Each file, listed side by side, with additions and deletions and amendments clearly highlighted.  You can scroll up and down, or left and right, and everything stays in sync.

Exam Diff also comes in a Pro version, which costs money.  However, the basic version is free and does all that you might require of such a utility.  It's a 0.5 MB download from http://www.prestosoft.com/edp_examdiff.asp [3] and runs under all recent versions of Windows.  It's malware-free according to VirusTotal and Web of Trust.  

You'll notice that the download page has lots of links to the file, from various hosts.  I chose the top one (version 1.9 from Prestosoft, EXE).  I have no reason to doubt that the other versions are also malware-free, but choose the first option if you want the same file that I checked.