How to prevent unauthorized computer access

Updated: 11/13/2018 by Computer Hope

Most users are interested in taking steps to prevent others from accessing their computer. Whether it be to protect yourself from malware or ensure that your private information is safe, having a secure computer can provide peace of mind. The following sections detail many ways you can secure your computer against others. To proceed, you may read through each section or choose one that interests you from the below list.



Make sure a password is set for your computer's operating system. The best way to keep someone out of your accounts and personal information is to not let them on your machine in the first place. You can always create additional accounts for guests. For additional information, see the following linked pages.

Helpful password tips

  • Never keep a default password. Passwords such as "password," "root," "admin," or no password at all allow easy access to your computer or Internet accounts.
  • Change passwords often. It is recommended at least once every few months.
  • Create a BIOS password.
  • When creating a password, add numbers or other characters to the password to make it more difficult to guess; for example, 1mypassword23!.
  • Do not use sticky notes around your computer to write down passwords. Instead, use a password manager.

Get a hardware or software firewall

Picture of 3Com SuperStack 3 Firewall

We highly recommend that all computer users have a firewall solution. There are two ways a firewall can protect your computer and network.

  1. Hardware firewall - A hardware firewall is a physical device that is connected to your network. Often, many users who have a home network can use their network router as a firewall solution. A good example of a network security device with a firewall and other security options is the ZyXEL ZyWALL (shown right).
  2. Software firewall - A software firewall is a software program that you install on your computer to helps protect it from unauthorized incoming and outgoing data. A software firewall will protect only the computer on which it has been installed. Additionally, many antivirus scanners include their own version of a software firewall. See the antivirus section on this page for more information.

Microsoft Windows firewall

If you are running any version of Microsoft Windows after XP, there is a firewall built into your operating system.

Other firewall programs

If you are not using the Windows firewall, a hardware firewall, or a firewall that is part of your security software you can also purchase a firewall standalone program.

Operating system and software patches and updates

Software updates

There is no such thing as perfect software. Programs often have compatibility issues or vulnerabilities that can compromise your computer's security. Software patches, updates, and drivers are made available, often for free, to consumers to help keep a software program and operating systems running properly and secure.

If the program you're using does not have any method of checking for updates on its own, it is up to you to verify the program is up-to-date. Often this can be done by visiting the website of the developer who created the program. A listing of third-party companies and links to each of their pages is on our third-party support page.

Malware protection

Computer Virus

Trojans, viruses, spyware, and other malware can monitor your computer and log keystrokes to capture sensitive data such as passwords and credit card information.

To help protect your computer from these threats, we suggest installing both virus and spyware protection programs.

Run system scans to check for vulnerabilities

There are several online sites that can help check computers for potential threats. Either of the below services will scan your computer for vulnerabilities.

Gibson Research Corporation - The Gibson Research Corporation, or GRC, is operated by Steve Gibson. It offers information and advice about network security and several tools to help test for vulnerabilities in your computer or network.

Know how to handle e-mail


Today, e-mail is one of the most popular features on the Internet. Being able to identify threats sent through e-mail can help keep your computer and your personal information safe. Below are some of the most common threats you may encounter while using e-mail.

  • Attachments - Never open or run e-mail attachments from addresses with which you are not familiar. Viruses, spyware, and other malware are commonly distributed through e-mails that have attachments. For example, an e-mail may want you to open an attachment of claiming to be a funny video, when it's a virus.
  • Phishing - Phishing or an e-mail phish is a message that appears to be from an official company (such as your bank) indicating you need to log onto the site to check your account settings. However, the e-mails are really sites set up to steal confidential information such as your passwords, credit card information, social security information, etc. See the phishing definition for additional information about this term as well as examples of these e-mails.

Alternative browser

Before the release of Microsoft Windows XP SP2 and Internet Explorer 7.0, Microsoft Internet Explorer was notorious for security and spyware related issues. Although it has improved since then, we still highly recommend considering an alternative browser such as Mozilla Firefox or Google Chrome.

Additional information