What are you to do when you have a computer problem so bad that your computer won’t start at all and you’re pretty sure a virus or some other malware is to blame? How do you scan for viruses when you can’t start Windows to do a virus scan? This is where a bootable antivirus program becomes the hero of the day.
With a bootable virus scanner, you create a special flash drive or CD/DVD disc from a working computer and then use it on the infected machine to scan the hard drive for viruses – all without needing to start Windows! Since the most serious of viruses cause damage to the parts of your computer that allow it to start, a bootable antivirus tool can often be a powerful weapon at your disposal for getting the virus removed and your computer back up and running.
Note: In general, getting a bootable antivirus program up and running requires that you take the ISO image provided and then, from a working computer, burn it to a disc or burn it to a USB drive. Next, you’ll need to boot from the disc or boot from the flash drive on the infected PC. More details are available in my reviews and on the bootable AV program websites
Adaware has this free bootable antivirus scanner that’s a breeze to use. You can update it before starting scans and it has a full user interface just like desktop-based programs. There are multiple types of scans you can run, so whether it’s a quick check for a boot sector virus or you want to find malware in specific folders or the whole computer, you can do it all with this program.
Anvi Rescue Disk is a really simple bootable virus scanner. There are only three main scan buttons, two sections to the program, and no custom settings. You can run a quick smart scan, a full system scan, or a custom scan to search for malware inside one or more specific folders. There’s also a section for finding and correcting corrupt registry issues that may have been altered by a virus. The only thing I don’t like about Anvi Rescue Disk is that you must scan the whole drive at once – you cannot choose to scan single, specific files like you can with regular antivirus software.
AVG Rescue CD is a text-only free bootable antivirus program. It can check for potentially unwanted programs, scan cookies, find hidden file extensions, and even scan inside archives. Before you start a scan with AVG Rescue CD, you have the option to just scan a folder of your choice, just the boot sector, only the registry, or any locally attached hard drive. Unfortunately, because AVG Rescue CD doesn’t provide a graphical interface, navigating the menus can become difficult.
Avira Rescue System is a free bootable antivirus program that also functions as a registry editor, web browser, and more, all under a standard graphical interface. Avira Rescue System automatically updates its definitions before performing a scan, which is great so you don’t have to re-download the software every time you wish to use it. During a virus scan, compressed files are unpacked and scanned for added protection. Avira Rescue System doesn’t let you scan individual files, but only a whole partition at once, which is too bad. Also, the download is rather large at around 630 MB.
Bitdefender Rescue CD is a free bootable virus scanner program that automatically checks for updates every time it’s launched. You can exclude certain file extensions from a scan, choose the maximum file size Bitdefender Rescue CD should scan, and optionally include archives with a scan. Bitdefender Rescue CD lets you search in individual folders if you wish to target a specific directory and not the whole drive. One thing I don’t like about Bitdefender Rescue CD is that it takes quite a long time to start up when you boot into the program.
In addition to the regular, installable Comodo Antivirus software, Comodo also has a free bootable antivirus program. Comodo Rescue Disk can be launched from a USB device or disc in either text-only mode or with a full graphical user interface (GUI). The GUI version has a familiar program interface that is much easier to use.
There are three different scan types you can start with Comodo Rescue Disk: smart scan, full scan, or custom scan. Smart scan checks for viruses and rootkits in the memory, boot sectors, autorun entries, and other areas like the registry and system folder. A custom scan lets you choose individual files and folders to scan instead of an entire drive. You can also scan archives, enable heuristics scanning, and skip files over a specified size.
Dr.Web LiveDisk is a feature-filled free bootable virus scanner for Windows and Linux. There are plenty of configurable settings, like choosing the actions Dr.Web should take when finding infected, suspicious, or incurable files. Also, you can set what should occur in the event it detects specific issues like adware, dialers, jokes, hacktools, and riskware. You can also exclude directories from being scanned, set how large a file can be before it’s excluded from a scan, and define a maximum duration Dr.Web is allowed to spend scanning a single file.
I like that Dr.Web can check for virus definition updates directly from the program. This means you can reuse the program in the future and all you have to do is update it before you do a scan. You can install Dr.Web LiveDisk to a USB device or a disc, but either method is still a rather large download, at 600 MB in size.
F-Secure Rescue CD is a simple bootable antivirus program. It works without any graphical user interface, so it may be a bit confusing. There are hardly any options or user input except pressing the Enter key to confirm the start of a scan. F-Secure Rescue CD updates its virus definitions automatically before starting a scan but it’s unfortunate you can’t skip over them.
Kaspersky has what’s called a Rescue Disk, which can scan for viruses, worms, Trojans, malicious tools, adware, dialers, and other malicious items. You can use graphical mode (recommended) or text-only mode to use the program. There’s an option to scan inside archives, check installation packages, and scan OLE objects. Heuristic scanning is supported and you can choose one of the three-mode types for deciding how deep Kaspersky should scan.
You can also set Kaspersky to automatically disinfect your computer when it finds a malicious item or to simply prompt you to take action. The only downfall I can find with Kaspersky Rescue Disk is that the download file is rather large, and may therefore take some time to download.
Panda Rescue ISO is a program that allows the free Panda Cloud Cleaner program to scan a computer without any interruptions. Panda Rescue ISO is simply a means of launching the Panda Cloud Cleaner program by itself, without any other running processes that could potentially shut it down and prevent a virus scan.
First, you must boot to the Panda Rescue ISO disc to prepare your computer for running Panda Cloud Cleaner. Next, your computer will reboot into Windows but launch the cleaner before any other applications launch. All other processes are shut down so Panda Cloud Cleaner is less likely to be terminated by a virus. The problem I have with this tool is that it may not work properly if a virus has infected your computer so deeply that you can’t even boot into Windows. If this is the case, you’ll want to try any of the other tools in this list that don’t require Windows to boot.
This utility is a bit different than the others in this list because PC Tools’ Alternate Operating System Scanner is a portion of a larger suite. The whole suite includes not only a virus scanner but also a system shell, file manager, data destruction utility, and file recovery tool. If malicious files are found, PC Tools’ Alternate Operating System Scanner will show a results page where you can disable them so they can’t do any harm to your other files.
The main thing I like about this tool is that there aren’t any custom settings (which could be a good or bad thing depending on your perspective). It works as quickly as choosing the drive to scan and then waiting for the results.
Not many custom settings or options are available in Sophos Bootable Anti-Virus except choosing one of two different scan types. A Recommended Scan can either rename infected files or just display a log of the malicious items that were found. An Advanced Scan will actually remove any infected files it detects.
There’s also a Bash Shell menu option for manually removing viruses. This option is only useful if you know where the malicious items are, which isn’t very likely. Note: Advanced steps are necessary to get the Sophos Bootable Anti-Virus ISO file. You must read the instructions carefully in order to download the program. It ends up requiring around 190 MB of free space.
Trend Micro Rescue Disk is another free bootable antivirus tool that doesn’t have a graphical interface, meaning you’ll need to navigate entirely in text mode with the arrow keys. You can run a quick scan or a full scan depending on what areas you’d like checked. Note: Trend Micro Rescue Disk is first downloaded as a regular program file that includes the bootable software. Just choose to install it on a USB device or CD.
VBA32 doesn’t support a graphical interface but it makes up for it in its detailed settings. There are plenty of options in this program, like choosing which drives to scan, defining a set of file types to scan, choosing to scan inside archives, and deciding a default action when a malicious file is detected.
You can also adjust the heuristic scan settings and update virus definitions directly from the CD or USB drive. The obvious downfall to VBA32 Rescue is that you must use it in a text-only mode, unlike most of these other tools that have a regular, graphical interface.
From Microsoft, Windows Defender Offline is a bootable virus scanner that sports a full user interface. You can update the virus definitions directly from the disc, view quarantined files, and exclude files, folders, and extension types from scans. Windows Defender Offline supports quick virus scans, full scans, and custom scans so you can choose your own folders and drives to scan. Note: The Windows Defender Offline tool from the download link can burn the software to a disc or USB device for you so no image burning software is necessary.
Zillya! LiveCD can scan entire drives or whole folders only, but cannot scan just single files. There’s an option to check for viruses in potentially dangerous file types like executables so you’re not scanning every single file type, which could take a long time. A utility called Zillya! MBR Recovery is available from this bootable disc, which can scan the MBR for viruses and attempt to fix boot issues caused by a corrupt MBR. I like all the settings that are included in Zillya! LiveCD as well as the fact that it provides a very easy-to-use interface.