Top Answer
User Avatar
Wiki User
Answered 2008-12-28 19:10:14

Because of the way that operating systems access files, only one program can access a file at once. If a file is being used by another program, or is a system file that is constantly used whilst the operating system is running then the virus scanner can't access it to fix it.

A boot time scan is a virus scan that is run before the operating system fully loads up. This means that the virus scanner can have access to all the files on the computer with no chance that they're being used by another program or the operating system.

This means it is much more likely to find and fix viruses that have affected critical system files, like the contents of the c:\windows folder on the windows operating system.

User Avatar

Your Answer


Still have questions?

Related Questions

How do you start boot time scan?

1. Make sure you have the latest version of Avast and the latest virus definitions 2. Open the Avast UI 3. Go to the "Scan" tab 4. Select "Boot time scan" from the dropdown menu 5. Click "Start" and next time you boot up a boot time scan will start

In order to protect your computer from the newest viruses should you do after you've installed virus scan software?

After a first-time install... Re-boot your computer into 'safe' mode. That stops most programs running - and loads just the minimum drivers to make the computer usable. Run an update of the anti-virus program -to download the latest virus definitions. Run a FULL scan with your anti-virus program - which will check almost every part of the hard-drive. Assuming the program has the option - run a 'boot-time' scan - which will analyse parts inaccessible under normal operations. Once you've run a full scan, and presumably the program has returned no virus detection - re-boot your computer in 'normal' mode - and you're all set

How do you find boot time scan file in quick heal?

Quick heal is a type of DNA scan on a computer file. This helps to remove issues and do a clean boot of the computer.

Can a security scan be use in computer even if there is already an antivirus scan?

You can run an antimalware scan and an anti virus scan at the same time with less chance of conflict.

How often should you do a virus scan on your computer?

Most anti virus programs do a automatic scan at a set time, which I would recommend to set to daily. Usually they will do this in the background. It is recommended that you do a full system scan every 1-2 weeks!

If you downlod a PC game can you a get a virus on your computer?

If you download many PC games then you could get a virus from it. Just scan your virus program every time you download anything.

I have 360 Gb hard disk i cant open the disk any computer and If i am going to do scan with AVAST anti virues there is no progress. kindly suggest me what i want to do...?

There is a boot time scan in Avast antivirus. Schedule the boot time scan and restart the PC Avast will try to fix the virus problems before the user authentication window. Note: Make sure that you should not delete the system files when Avast scanner has detected the system files as corrupted. Like explorer.exe , svchost.exe etc. If this has not fixed the problem, then download a live cd for windows and boot from it. Backup all the data and reinstall the windows.

What sfc command sets the system to scan system files at every reboot?

sfc/scanboot the above is only if you want it to scan every time the computer reboots. if you want it to only scan the next time you boot the command is sfc/scanonce

What can you do if your computer is getting ads streamed directly to the computer?

You may have a virus. Some will not be detected by regular scanning. Check and see if your antivirus has a boot time scan option. If it does, turn it on and restart. May wanna wait till you are ready to go to sleep because it will take some time to complete.

What should you do after installing a virus scan to protect your computer from new viruses?

On first installation - before running the anti-virus for the first time, re-boot the computer into safe mode for better detection. Safe mode only runs the minimum drivers needed to make the computer functional. This means there's more chance of detecting any virus that's been hidden in any 'auto-run' programs. Once you've scanned in safe mode (and assuming nothing was found) you can re-boot as normal.

How do you know if the computer has a virus?

It is very slow despite good specs. Random things pop up ALL the time. Scan it with malwarebytes virus removal tool.

How is a quick scan different from a full system scan?

A quick scan just scans most commonly infected files on your computer. That saves you time, and is just fine when you have no reason to be concerned that you have a virus. A full system scan will scan everything in your computer, which is necessary for some more extreme viruses, but it takes longer.

Does Norton scan your whole computer?

Hmm yeah it can and usually does im not that familliar with norton though if you want a great free anti-virus Avast is great it even does boot time scans that means before viruses can start up their protective shield that may hide it, Avast scans

If you have a virus in Winlogon what can you do?

I hate winlogonBoot into safe mode with CMD, since windows isn't running you can delete the .dll that's running on winlogon. If you know the path to the file that you need to delete, good - if not, you should be able to get that info from your HJT scan. Also you can use Knoppix, a distribution that boots and runs completely from CD and can read/write to ntfs.Also you can try killing the winlogon process and delete the worm, without usig any boot disk or recovery console.Read step by step istructions here: use malwarebytes antimalware to remove the winlogon Or download anti virus called "avast anti virus" doesn't matter pro version or the free version hes good at free almost as the pro one.when you finished downloading and installing.. just time a boot scan then it will restart your computer and start scaning for viruses and malwares from boot before windows starts which means no dlls loaded and no proccess started then the anti virus will remove the intruder.It worked for me perfectly my anti virus always saves my me.

Does mugen has a virus?

Do you mean MUGEN the game? NO, it does not. I have it on my computer, it works fine and it rly fun! It might have a virus if you downloaded it from an unknown site. To check to see if the program you downloaded has a virus, download AVG from and scan the file with it. If it is a virus, then delete it and next time download Mugen from

If your AVG antivirus is set to do a scan at a time when you are not online does it still do the scan?

Yes if AVG is scheduled to run the scan at a particular time it will run the scan .

Why is it that you have to virus scan your computer daily?

Because viruses can appear at any time of any day. It's important to catch any viruses in time before they do serious damage to your computer.

How can you recognize which downloader virus is in your computer and what steps to be taken to remove it?

First try scanning with Free software, such as Avast home edition. then try a boot time scan. If not removed then try a SmithFraudFix, make sure you read the README.txt for help If still not removed try a hijackThis, and get help from the many forums that take hijackthis logs.

Why does your firewall keep turning off every time you turn it on?

Maybe it has a different firewall turned on, that could be why. You are infected with a virus and the virus is turning it off. Start your computer in Safe Mode and run a full scan with your antivirus software.

is there any free online virus scan available?

Yes, most of the big name virus scanners have an online version for you to try out for free. Try out mcaffe or some other brand, last time I check they did have it. Good luck.

Does antivirus program check all files for viruses during the boot process?

No. some anti virus programs never check at boot time. others check some areas like, memory. but no antivirus check for all files at startup.

How do you figure out the virus?

If you do not have anti virus software, download ASAP. Run PC scan through anti virus to locate and quarantine the virus. If you don't have and don't want to download anti virus software, figure out when your computer started showing signs of infection. Did you download something or go to an untrusted site around that time? If so, you can uninstall the program you downloaded and go into your control panel and restore a checkpoint from before the infection. However, some viruses are very tricky. You can run your PC scan to learn the name of the virus. Type the virus name into your search engine and it will give you different resolutions on how to remove it safely.

How do you remove Bloodhound W32 EP which has become resident on your computer running Windows XP?

1) Turn off System Restore - then Reboot 2) Uninstall whatever anti-virus software you are currently running. Reboot 3) Download free Avast! Anti-virus Home edition 4) Set it to Run a "Boot Time Scan" - Reboot 5) Select "Delete" to any of the prompts that come up by pressing: 1) Delete 2) Delete All (this is the preferred method so you won't be asked again) The scan should take 15 to 45 minutes to complete

What is the process to remove virus from a virus affected computer?

Which anti-virus program do u use??? Use AVG anti-spyware v.7.5+... Go in the scanner tab click on 'complete system scan' give it time to complete... and delete the virus that come in the list of infected objects... If u have any further queries mail me on

How do clean a virus from a computer?

Run a virus scan using AVG free (can download at web address below) and then at the end of the virus scan (can take up to 4 hours depending on hard drive size and CPU speed) and then at the end you should get an option to remove all viruses found or it should (most of the time) do it automaticly.