Portable apps are incredibly convenient – particularly security tools. They don't have to be installed, and are optimized for use from a USB stick, portable hard drive or cloud storage service. This means you can use your chosen security and privacy programs on any PC, at any time. Portable apps don't leave any files behind after you've closed them down, and won't conflict with software already installed.
Another benefit is that portable apps are usually supplied in a simple ZIP archive, not bundled with any potentially unwanted programs (if such an app has an 'installer', it will only extract the executable file and let you choose where to save it).
Here, we've gathered our favorite portable apps for keeping your data secure and your privacy intact. As with any security software, make sure the programs in your portable toolkit are kept up to date. Most should update themselves automatically when run on an internet-connected PC, but also keep an eye out for the developer's release notes.
KeePass Professional Portable
One of the cornerstones of security is a strong password, but remembering multiple passwords, each one containing letters, numbers and special characters, is a real challenge - especially if you update them as often as you should.
KeePass Professional Portable (also known as KeePass 2) offers an alternative by enabling you to store all of your passwords in one secure, encrypted database - you need only remember one master password.
Once you have the program running in the background, you can use a keyboard shortcut to fill in username and password fields on websites and in programs automatically. There's no need to even open the app to copy the relevant password - KeePass can do it all for you automatically.
This is reason enough to recommend it, but extras such as a powerful password generator make it indispensable. Read on for the rest of our portable security toolkit recommendations.
Local Area Security Audit Tool
Local Area Security Audit Tool can scan not only single computers for security issues, but multiple networked machines as well. It's designed with advanced security testing in mind, but is also useful for home users who want to identify weaknesses in their setup.
Unlike many of the tools in this kit, which are designed for use in an emergency once a PC is already infected, Local Area Security Audit Tool is a prophylactic measure. It won't fix security issues, but its in-depth scan will reveal what sensitive information on your PC or network could be accessed by malware.
These include stored passwords, address book entries, wrong security configurations, browser history, cookies and much more. The results can be eye-opening; you'll see just how many passwords your browser is storing, and be warned if you're going about your daily business with an Admin account. The issues it finds are almost always easy to solve, and doing so could save you serious hassle further down the road.
We recommend only running Local Area Security Audit Tool on your home LAN; you might attract the ire of your company IT department if you begin scanning their corporate network.
Norton Power Eraser
Norton Power Eraser is a free rescue tool developed to remove malware that your regular antivirus program may miss. It specialises in 'scamware' - fraudulent programs that claim to have discovered a critical problem with your PC that can only be resolved by downloading something nasty, or by paying a fee.
If you're suddenly seeing popups or notifications from a program you don't recognise, open your toolkit and set Power Eraser to work.
Power Eraser can also scan for more benign (but nevertheless irritating) potentially unwanted programs, which are easy to download accidentally alongside legitimate free software.
For a more targeted diagnosis, the advanced options let you perform a Reputation Scan on a file or folder you suspect may be harboring malware. This scan aims to detect new threats as soon as they arise using data from thousands of other Norton users.
If you have more than one bootable operating system on your PC, you can also specify which one to scan (though this only works with multiple instances of Windows).
Read on for more essential portable security downloads for your toolkit.
McAfee Stinger is another excellent portable rescue tool, and is ideal if you think that you might be dealing with a virus or rootkit.
Before performing a scan with Stinger, you'll be prompted to close all other running applications on your system, so make sure you save any work before proceeding.
Stinger now includes a real-time scanner that looks for new infections, but this is still in beta and shouldn't be relied on to keep your system safe. We recommend installing a tool like Avira Free Antivirus or Avast Free Antivirus for real-time protection, and keeping Stinger on a portable device for emergencies.
Comodo Cleaning Essentials
Comodo Cleaning Essentials contains an excellent malware scanner, but its real attraction is Killswitch (which you'll find as a separate application in the same ZIP archive) which can identify and terminate unsafe processes running on an infected PC.
Killswitch scans all the processes currently running on your PC, and flags any that might be malicious. It can also check the programs running and show you their resource usage (ideal if your PC has suddenly slowed to a crawl for no apparent reason), and let you manage the applications that start at the same time as Windows.
Bear in mind that stopping Windows Explorer will leave you without a desktop until it restarts, and terminating drivers will cause the associated hardware to stop working.
Some other free portable security apps to consider adding to your tookit:
CCleaner Portable - Clear your search history and cookies to protect your privacy and free up system resources.
Tor Browser - Not a security app as such, but if you need to use a PC that's not your own, this self-contained browser will keep your activities private and leave no trace once you've finished.
Omziff - File encryption, secure deletion and random password generation, all in one tiny portable package.
Can you suggest any other software for a portable security toolkit, or good alternatives for the ones we've suggested? Let us know in the comments below.