First, on the computer from which you want to share the file, open the HomeGroup control panel. If a homegroup does not already exist (Windows may have created one automatically when you first set up Wi-Fi), click Create a HomeGroup. Choose the file types you’d like to share (‘Documents’ is not selected by default), and click Next. You’ll receive a password for the homegroup. Write it down.
Wait a few minutes for Windows to update everything. Then, on the other computer, open the HomeGroup control panel, and you should see the homegroup you just created. Click Join now and follow the rest of the steps in the wizard. The computers will share files with each other from now on.
To find the shared files, in Windows Explorer look for your homegroup in the left pane. The other computers that you have added to the network will be listed there, and the shared files will appear in the right pane.
If you ever wish to change your homegroup password, open the HomeGroup control panel on a machine that is already in the group, and click Change the password.
Accessing files on a Mac from a Windows 7 PC: On the Mac, visit System Preferences and open the Network application. Click the WINS tab. Change the ‘Workgroup’ setting to the same Workgroup your PCs use. (If you’re not sure of the name, you can find this setting listed in your PC’s System control panel.) Click OK.
Still in System Preferences, open the Mac’s Sharing application. Place a checkmark next to File Sharing. Over in the Shared Folders pane, select the folders you wish to share. In the Users pane, give rights to each folder as appropriate, assigning either Read Only or Read & Write to the ‘Everyone’ group.
Next, click Options and then put a check in the box for Share files and folders using SMB. Click Done. Lastly, open the Accounts application, unlock your system, and click Guest Account in the left pane. Check the box next to Allow guests to connect to shared folders.
In Video: How to Set Up a Windows 7 Network
Troubleshoot Network Outages
5 minutes Numerous circumstances can cause your network to go dark. Follow these steps to fix it. (These tips presume trouble with wireless networking but largely apply to wired networking, too.)
If you use a USB-connected networking device, unplug it and then plug it back in. USB Wi-Fi sticks are notoriously finicky. Next, reboot your router by unplugging it, waiting 30 seconds, and plugging it back in. You may want to reboot your system while you wait. This procedure will fix the vast majority of lost-network problems. Didn’t work? See if other PCs on the network can access the Net. If not, your ISP may be having an outage. Try rebooting the cable or DSL modem.
Also, check your machine’s IP address to make sure that the router is properly configured. Choose CMD from the Start menu (type CMD in the search box to find it quickly) and type ipconfig /all. From there, find the proper adapter (you may need to scroll up) and look at the ‘IPv4 Address’ item. If you have a typical home setup, the first three numbers (separated by periods) should be the same as those of the DHCP Servers. If not, you may need to reconfigure or reset your router, which could have become corrupted.
If you’re using Windows Firewall (or another software firewall), it might be interfering with network access. Try turning it off (you can find Windows Firewall in the Control Panel).
Finally, if you’re on a wireless network, try plugging in an ethernet cable and connecting your computer directly to the router. If this works, you likely have a problem with the wireless adapter’s driver. Try updating the driver manually by downloading it from your computer manufacturer.