After downloading netscan.exe, double click it to run the program. (No need to install anything.)
First, you’ll need to change the account Network Scanner uses. From the Options menu, select Program Options. Then click the Shares tab and at the bottom of the window select Use specific account. Enter some dummy username and password combination such as guest/guest. Click OK to save the settings.
Next, enter the IP address range you’d like to scan in the two boxes at the top. Click the Start Scanning button to launch the scan. The main window will quickly fill with all the systems Network Scanner can ping on the IP address range you provided. Any systems with open shares will have a plus (+) shown at their left. Clicking on the plus show all the open shares on that system.
Last, you need to check for any false positives and connect to the open shares found by Network Scanner. Try to open the share with an unprivileged account and see if you get access. An Access Denied error just means that Network Scanner could see the share is there, but not actually view the contents of the share. A folder full of confidential information means you need to restrict permissions on that share.
Have fun kicking around the soccer ball.