Share your screen, or help a friend

If you've ever found yourself wishing you could show a friend your computer screen or take over a computer for low-budget support, these free screen-sharing apps may be right up your alley.

Have you ever had to talk a relative through a complicated computer task?

"OK, start by opening a command prompt."



Support professionals--such as our IT team at CNET--employ software that lets them access PCs and fix problems remotely. However, Uncle Bob's lost photos are just as important as a VP's lost e-mail.

If you're ever in a situation where you want to control another person's PC or let a friend access yours, there are several excellent software programs that allow you to do so. Most are based on the open-source Virtual Network Computing software developed by AT&T. In fact, one VNC project, VNC Free Edition from RealVNC, is led by one of the main developers from the original VNC team.

Most of the apps let you specify exactly how much control of the remote PC you want to allow. You can either simply display your screen to a friend or give him equal control of your machine.

Even better, some of these freeware apps will also let you transfer files between two PCs. Even if Uncle Bob loses his photo album, if he's sharing with you, you can always keep a backup.

Read about some of my favorite screen sharing applications from CNET, and then be sure to tell me about your favorite software or methods in the comments.

VNC Free Edition (Credit: CNET Networks)

VNC Free Edition

As mentioned above, this free product has the experience of Andy Halter as the company's current CEO. Halter was one of the original developers on the VNC project.

VNC Free Edition provides a bare-bones way for hooking up two PCs using the VNC protocol, but that's about it. The options are straightforward enough and let you specify exactly what type of remote inputs your computer will take.

However, connecting to another machine is a different story. You're basically on your own when it comes to finding the other VNC machine that you're looking for. You can use products such as No-IP to create artificial domains that you can use to connect, or you can use a current IP address.

It's a simple program that works well, but it's hard to recommend it for inexperienced computer users. The free version also does not allow file transfers, a major missing feature.

One of the options in VNC Free Edition is to install the program as a Windows service, and I don't recommend it. I had much more success connecting to remote PCs when it wasn't running as a service, though your results may vary.

CrossLoop (Credit: CNET Networks)


This excellent little freeware app is one of the easiest and quickest ways to share one screen among two distant users, and it's simple for a newbie to start it up and be using it successfully within minutes.

CrossLoop works uses the same VNC protocol, but doesn't require any special firewall or router configuration. It uses the TightVNC software plug-in for screen sharing, as well as proprietary, peer-to-peer tunnel technology that lets you share files and messages with connected PCs.

The software consists generally of two tabs for "Join" and "Host." When you decide to host a CrossLoop session, you'll be assigned a secret access number. Only people who have that number will be able to access your PC.

The latest update to CrossLoop added some very cool and very valuable features, including the ability to transfer files directly via P2P. All data on the CrossLoop network is encrypted at endpoints using the 128-bit Blowfish algorithm.

Version 1.11 also added the ability to switch between Join and Host with a single click, as well as the option to specify exactly how much control of your PC you're willing to give up. "View Only" and "Share Control" are two new session settings.

UltraVNC (Credit: CNET Networks)


A bit like VNC Free Edition, UltraVNC includes a few more valuable features, but it's also not very easy for a new user to get set up and running.

The most-valuable feature lets users transfer files between the two connected PCs. The second-most-valuable feature lets a user connect to a UltraVNC enabled PC via a Web browser, using the URL http://remote-machine:http-port/ where the remote machine is the name of the computer you want to connect to.

TightVNC (Credit: CNET Networks)


If you're sensing a trend in these X_VNC clients, you've got a good eye. Much like VNC Free Edition from RealVNC and UltraVNC, TightVNC works very much like a basic VNC connection tool.

You'll need to have either an IP address or domain name for the computer that you'd like to access, and that computer must be running a VLC Viewer app that is "listening" for connections.

TightVNC does include a few customization options that distinguish it from UltraVNC or VNC Free Edition. The most notable may be the Display setting, which lets you specify exactly how much of your screen a remote user can access: full desktop, primary display, a rectangular area, or a specific window.

TeamViewer file transfer
TeamViewer file transfer (Credit: CNET Networks)


Much like CrossLoop, this polished and full-featured app is designed for users with no previous knowledge of VNC connections.

Each computer that installs TeamViewer will receive a specific ID number. In order to connect to a computer with TeamViewer installed and running, a remote user will need both that ID number and a session-specific password, which seems to usually be a four-digit number.

TeamViewer runs off of an infrastructure based on UltraVNC, and it also uses a companion program callled DynGate to channel the TCP/IP data of your VNC connection through an HTTP tunnel.

Once connected, the remote computer will appear in a standard remote-access window that includes several valuable functions in a sliding bar at the top: stop connection, refresh screen, customize settings, initiate a chat window with the shared computer, open the file-transfer tool, disable remote input, select a single window, switch remote-access between computers, and toggle between normal and autoscaling modes.

The coolest feature of TeamViewer might be the built-in file- transfer tool, which looks a lot like your common FTP client. Each PC's directory sits side by side, and files and folders can be transferred with a few simple clicks.

I did notice that the graphics in the remote viewer were much grainier with inaccurate colors. The problem can be alleviated by selecting "Optimize quality" under the "Display Settings" in the "Connection Options," but it still might be an issue to consider if design is a critical component of the remote-access session.

ShowMyPC (Credit: CNET Networks)


This simple app runs directly from a standalone executable, and it requires no installation. Just double-click the program to allow someone else to access your computer or vice versa.

Like TeamViewer, the software is built on top of UltraVNC, and connecting to another machine is about as easy as it gets. The app consists mostly of two buttons: "Show My PC to Remote Users" and "View a Remote PC."

If you click the first button, the software will generate a 13-digit key that you can share with any other ShowMyPC user to give him access to your PC. Likewise, clicking "View a Remote PC" will spawn a pop-up window asking for such a specific password.

When connected, the VNC application works great, with helpful buttons at the top of the screen that allow easy access to the "Ctrl-Alt-Del" and Windows "Start" menus. However, I must note that I had several problems when trying to connect to remote computers. Several times when connecting, ShowMyPC would force a hard restart of my machine, losing all of my unsaved work. Also, the client is very version-specific. If you or the person you're connecting with is using an outdated version, the connection will likely fail.

Tell me about your favorite screen-sharing software.

So, how do you share your screen or provide computer support remotely? Tell me about your favorite software and methods in the comments.

About Peter Butler

Peter has been working at since 2003, when trialware was shareware and toolbars were those large metal rods for smashing car windows. Currently, he wrangles the reviews, videos, newsletter, blog, and special collections for, as well as managing the program data throughout the software directory.