DFStack is a program that lets you decode call stacks reports of programs that were obfuscated with Preemptive Dotfuscator tool. When you obfuscate a program you change the name of all the objects and methods of your code. This is great to protect your intellectual property, but in exchange when a client reports you a typical error with the call stack that caused the error, this stack is also coded in the same way, so to fix the error you need something to decode it and get the real stack.
DFStack uses the Dotfuscator map file created when you obfuscated your program to decode the stacks easily. You just select the map file, paste the obfuscated stack and click on decode to get the stack translated.