The 8 Useful DOS Commands That You Should Memorize

By Ryan Dube on 4^th May, 2011 | Windows |  26 Comments

I realize that providing a lesson on DOS commands to MUO readers is sort of like offering to teach a group of martial arts experts how to throw a punch. The thing is, there are quite a few people out there that don’t realize how easy it is to troubleshoot and fix certain computer issues using a few simple key entries. I’m not about to argue that DOS isn’t outdated. However, Windows 7 still features a command prompt window.

We’ve covered a number of current uses for DOS, such as  playing DOS games. I also provided some Windows Scripting tips, which is the next generation replacing DOS commands. With that said, there’s still a place for DOS commands. So, for those of you that like the idea of typing in a few commands to avoid the hassle of several mouse clicks, I’m going to review eight of what I consider to be the most essential and helpful DOS commands that are still available in Windows 7.

The DOS Prompt Window Is Not Missing!

If you are one of those folks that became convinced the DOS prompt was officially wiped out with Windows 7, all you have to do is click on the Start menu, and in the “Search programs and files” field, just type “cmd” and press enter. Voila – there’s your DOS window.

Assoc: Associated Extension

Not sure what default program you have set up to handle ZIP, MP3 or HTML files? A quick and easy way to check for your default file associations is the “assoc” command. Just open a command prompt and type “assoc” followed by the file extension.

The response is the installed application that is currently configured to handle that file type. As you can see above, WinRAR is my ZIP file handler, MS Word handles doc files, and Chrome is set up as the default for HTML files.

Tree: View Directory Structure

If you’ve created a virtual spiderweb of files and directories on your computer, it can get pretty confusing to remember where everything is. Sometimes it would be nice to have a diagram showing directories and sub-directories. Using the Tree command, you can do just that.
First, navigate to the directory you want to get the file structure of, and then type “tree > myfile.txt“. The text file can be called anything you like.

The command writes the entire directory structure, completed with all folders, into the text file, which you can print out for easy viewing.

The formatting may look a little bit funky, but if you look closely you’ll see that the directories are all there, they just might be prefaced with some weird symbols.

File Search & Comparison

If you ever have two text files – particularly two very large text files – the file compare (fc) command is all you need to identify and synchronize file differences.
The usage is about as easy as it can get. Just type “fc” followed by the names of the two files.

The system will respond by showing the lines from both files where there are differences.  This command can become pretty handy when you’re collaborating with people and trying to sync up differences between files that several people are working on.
If you only need to find a file on your system, and you know the name of the file, the “find” command is far faster than any point and click operation you can do. Just do a “dir” command to the directory you want to search, and then “|” followed by the name of the file.

The system will respond with the directory where the file is stored.

Network Commands

I really don’t think there are easier ways available to do network troubleshooting than the sort of tools you get in DOS commands. For example, if you want to know your basic network setup, just do a quick “ipconfig” and you will get details like your computer IP and the default gateway (which is typically your home router IP address).

If you’re not sure you have a good network connection, try doing a “ping” to a known IP address or a website. You’ll see it echo back with an IP address if the link is good. If you want to see all network connections currently active from your PC, type “netstat“.

This shows you all network connections from your PC. It may be a good idea to search through these carefully to make sure that there’s no surprises in the form of malware or a virus hijacking your bandwidth.

Windows Utilities

Finally, there are a multitude of DOS commands that are invaluable as system troubleshooting tools. For example, to view a list of active processes, just open up a command prompt and type “tasklist“.

If you see any process you want to kill, just type “taskkill” follwoed by the image name.
Nervous about whether a particular system file became corrupted after a recent virus infection? Just type “sfc /VERIFYFILE=” followed by the full path of the file.

Windows will check to be sure it is the original. You can also scan all system files like this at once by typing “sfc /scannow”
Finally, probably one of the most useful DOS commands available – the AT command. With “AT”, you have the ability to schedule tasks to run on a regular routine, all from a simple command prompt.

Setting up the AT commands can be a little tricky, so type “at help” if you need parameter help. In the command above I set up the computer to automatically archive all files in the temp directory to the archive folder. You could do similar jobs to routinely back up important files on your computer to a mapped external drive.
As you can see, there’s still plenty that you can do with the command prompt. Having these resources at your fingertips can really make it a lot easier to troubleshoot, maintain and repair computer systems.
Were any of these commands new to you? Do you know of any other useful DOS tips? Share your insights in the comments section below.