Restrict Software Installs on a Shared Computer
" Short of disabling your CD drive and Internet link, there's no guaranteed way to block software installations. But the following suggestions worked with every Windows installation I tested.
With Windows 2000 and XP, you can stymie installs by having the only administrator account on the PC, if the account is password protected. In Windows XP, select Start, Control Panel, User Accounts. Click Change an account, your account, Create a password. (If you see a 'Change my password' option, the account already has a password.) Follow the instructions to create a password. The User Accounts window is where you create 'Limited' accounts for others who share the system.
In Windows 2000, press Ctrl-Alt-Delete, click Change Password, and fill in the form. Leave the Old Password field blank if you don't have one. When you're done, click OK, and then Cancel. To create other accounts in Windows 2000, select Start, Settings, Control Panel, Users and Passwords. Check Users must enter a user name and password to use this computer. Click Add to launch the Add New User wizard. When you're asked 'What level of access do you want to grant this user?' select Restricted user.
In Windows 98 and in Windows Me, you must use a third-party utility to keep other people from installing software. I recommend the $25 WinGuard Pro; you can download a limited-function trial version. After you install the program, click the Lock Programs tab, and then check both Registry Editor and System Configuration Utility (see FIGURE 1). On the Users tab, change the Setup Password and the User Password. On the Advanced tab, check Lock Software Installations. "