任何曾经在其计算机系统中感染过病毒的人都知道它的压力有多大。无论您是否拥有高级或强大的安全软件(advanced or strong security software)程序，病毒仍有可能突破其所有防御并感染您的机器。
计算机中可能感染病毒的一些最常见症状包括性能不佳或速度变慢(poor or slowed performance)、PC 行为不端、计算机死机或应用程序崩溃。但是，这些不一定是由病毒引起的，因为它可能是其他因素的结果。
在您真正扫描它之前，没有一种万能的原因可以让您查明并说这是您计算机中的病毒造成的。有时它们会引起问题，而有时它们表现良好但仍然在后台工作。
也就是说，如果你看到了所有的迹象，并且你的直觉让你问“我有病毒吗？”，我们将看看一些需要注意的主要和次要迹象，以及该怎么做从您的计算机中删除病毒以及防止未来攻击的预防措施。
什么是计算机病毒？(What Is a Computer Virus?)
计算机病毒是一种恶意软件(malicious software)，它锁定并利用您计算机系统中的合法应用程序代码进行自我复制和传播。部署它的目的是控制和/或损坏您的计算机。
计算机(Computer)病毒在许多方面与生物病毒具有相似的特征，包括它们如何从一台计算机传递到另一台计算机(pass from one computer to another)，以及搭载其他文件或程序来启动，以及其他特征。
每天，都会编写一种新病毒(Every day, a new virus is written)，其目的是伤害像您这样使用计算机浏览网页的普通人，而忽略了其中潜伏的危险。
黑客和诈骗者也变得更加狡猾和狡猾，他们巧妙地掩盖了他们的威胁，以至于单击一下就可以立即使您成为计算机病毒的受害者。
他们只需为病毒编写代码，然后对其进行测试以确保其正常传播，然后再将其发布以对计算机系统和其他设备造成严重破坏。他们还设计了可以采取不同形式的攻击阶段。
有些人这样做是为了看看事情是如何发展的，有些人只是想吹牛，而有些人则是为了当你被骗购买假软件或分享你的个人信息时他们可以获得的冷硬现金信息，他们用来窃取你的钱。
计算机病毒的工作原理(How a Computer Virus Works)
就像流感会感染并在您的身体免疫系统中繁殖一样，计算机病毒也会渗入您的机器及其程序。此类恶意程序可以在未经您同意或不知情的情况下安装在您的设备上，并且可以注入恶意代码，从而操纵和监控您在网络上的活动。
通常，病毒在感染您的计算机时采取以下过程：恶意应用程序应用户请求执行，病毒代码在执行合法代码之前被加载到计算机的 CPU 内存中。(loaded into the computer’s CPU memory)
一旦发生这种情况，病毒就会通过感染您的计算机程序和应用程序开始传播，并尽可能多地插入恶意代码。
根据病毒是否驻留在您的计算机中，或者它是引导扇区病毒，它可以在程序打开、可执行文件或系统磁盘的引导扇区中插入恶意代码，使其在您的操作系统之前执行完全加载。
此时，它将执行其创建者为其构建的病毒代码，也称为有效负载。然后，它会扫描您计算机的硬盘驱动器(scans your computer’s hard drive)以查找各种信息，包括您的击键(your keystrokes)、银行凭据，或者将您的计算机变成对他人进行DDoS 攻击的武器。(DDoS attacks )攻击者可以使用它来加密您的数据并要求赎金，以换取对您的文件和数据的恢复访问。
在互联网出现之前，病毒通过受感染的软盘或闪存盘传播，但今天，它们可以通过互联网传播，或者通过病毒代码在计算机之间传播。它们还可以通过电子邮件附件(email attachments)、应用程序或来自受感染存储库的下载进行传播。
警告信号表明您的计算机上有病毒(Warning Signs That You Have a Virus on Your Computer)
有许多不同类型的病毒(different types of viruses)根据它们的行为进行不同的分类，这意味着有些可以分为一个或多个类别。如果您强烈认为您的计算机可能感染了病毒，但不能完全确定它是否已通过安全软件的防御，那么这里有一些警告信号，表明您的计算机上存在病毒。
慢电脑
如果您的计算机启动或打开程序很慢，则很可能是感染了病毒。有几个因素可能会影响您的计算机的性能，但病毒是最令人担忧的，因为某些类型的病毒允许攻击者将其功能用于他们自己的非法目的，例如挖掘加密货币或进行DDoS攻击，所有这些都会影响其性能。
随机或奇怪的粉丝行为
计算机中的风扇有助于吸入冷空气，同时将热空气排出计算机机箱，并在游戏等资源密集型任务中超速运转。但是，如果您发现风扇的异常行为(strange behavior with the fans)，则可能是病毒感染的迹象，尤其是当计算机处于空闲状态时风扇仍以最大转速旋转或异常发热时。
频繁的计算机崩溃
这与蓝屏死机相结合，可能表明您的计算机存在病毒或问题。找出确切原因并不容易，因为有时它可能是由于过热、驱动程序问题、硬件问题或操作系统错误造成的。
网速慢
这通常归因于病毒和恶意软件，它们可以劫持您的连接并将您的带宽用于其他活动。如果您发现您的连接速度很慢或网络活动异常频繁(connection is slow or there’s unusual high network activity)，则可能是您的计算机感染了病毒。有时您可能会完全失去联系。
(Strange Browser Extensions)你没有安装(Install)的奇怪的浏览器扩展
如果您看到新的浏览器扩展程序看起来很奇怪，并且您不记得曾经安装过，那么您的计算机可能感染了病毒。某些扩展是合法且有用的，但其他扩展可能会收集您的个人数据并将其出售给第三方，或者将您的系统置于危险之中。
浏览器重定向
重定向在病毒感染中很常见，尤其是当您最终访问您不打算访问的网站时。此类网站通常带有恶意软件，并被用作从毫无戒心的用户那里收集个人信息的窝点，甚至鼓励他们下载更多恶意软件。有时它们被用来为此类网站增加流量，从而帮助网络犯罪分子从广告展示中赚取更多收入。
增加弹出广告出现(Popup Ads Appearing)在屏幕上的(Your)频率
如果您突然开始看到非正常频率的弹出广告，或者您的浏览器主页发生变化并且体验变慢，则您的计算机可能感染了病毒。一些不需要的程序通常带有广告软件，利用这个机会在快速致富计划、减肥和其他虚假病毒警告上显示不必要的弹出广告。
不规则的社交媒体帐户行为(Social Media Account Behavior)
当您的朋友开始收到据称来自您的垃圾邮件时，这是您的计算机感染病毒的另一个常见迹象。他们可能会从您的帐户中收到奇怪的消息或评论，这可能表明它已被入侵，或者您的计算机已被感染。
安全软件无法运行或无法正常工作(Work)
您的计算机的防病毒和安全软件(antivirus and security software)有助于保护它免受每天出现的新恶意软件的侵害。但是，某些毒株可以禁用它并阻止它运行扫描或更新，这是您计算机系统中病毒的明显迹象。
如果您发现计算机上的防病毒软件的行为与正常情况不同，或者您收到有关系统未受保护的警告消息，则您可能正在处理病毒。
如何从您的计算机中删除病毒并防止未来的感染(How to Remove Viruses From Your Computer and Prevent Future Infections)
从您的计算机中删除病毒并不容易，但您可以使用下面列出的部分或全部解决方案和措施来清理您的系统并使其恢复正常：
- 关闭(Close)消耗资源并导致您的粉丝加速的不必要的应用程序。检查它们是否恢复正常速度。
- 检查来自(Check)Windows Defender 安全(Windows Defender Security)性的关于您的防病毒软件是否已禁用的任何通知，并检查建议的解决方案重新启动(Restart)您的 PC 以重新启用您的防病毒软件，因为有时操作系统和软件更新会影响其功能。
- 从您的计算机和其他设备上的任何被盗帐户中退出
- 扫描您的计算机以查找恶意软件(Scan your computer for malware)。如果您有 Windows Defender Security并且它没有标记带有病毒的文件或程序，请尝试使用各种防病毒软件，因为它们都有自己的病毒库。这也是更准确地查看正在发生的事情的好方法。
- 安装反网络钓鱼浏览器扩展程序，以在您被重定向时阻止加载危险网站。卸载您一开始没有安装的任何此类扩展。
您可以采取其他措施来防止未来的攻击，包括更改密码(changing your passwords)、启用双重身份验证、在下载进入您的系统之前检查它们，以及安装可靠的安全软件(reliable security software)和良好的广告拦截(good ad blocker)器以获得更好的浏览体验。
HDG Explains : Do I Have a Virus? Here Are The Warning Signs
Anyone who has ever had a virus in theіr computer system knows how stressful it can be. It doesn’t matter whether you have an advanced or strong security software program, there’s still a possibility that viruses can get past all its defenses, and infect your machine.
Some of the most common symptoms of a possible virus infection in computers include poor or slowed performance, a misbehaving PC, computer freezing or application crashes. However, these aren’t always necessarily caused by viruses, as it could be a result of other factors.
There’s no one-size-fits-all cause that you can pinpoint and say it’s the work of a virus in your computer, until you actually scan it. Sometimes they cause problems, while other times they behave well but still work in the background.
That said, if you’re seeing all the telltale signs and your gut has you asking “Do I have a virus?”, we’re going to look at some of the major and minor signs to look out for, and what to do to remove the virus from your computer plus prevention measures to prevent future attacks.
What Is a Computer Virus?
A computer virus is malicious software that latches onto and rides on legit application codes in your computer system to reproduce and spread itself. It is deployed with the intention of taking control of and/or damaging your computer.
Computer viruses share similar traits to biological viruses in many ways including how they pass from one computer to another, and piggyback on other files or programs to launch, among other traits.
Every day, a new virus is written with the intention of harming regular people like you who browse the web using their computers, oblivious of the dangers that lurk therein.
Hackers and scammers too have become sneakier and trickier, cleverly masking their threats such that a single click can instantly render you a victim of a computer virus.
They simply write the code for the virus, and then test it to ensure it spreads properly before releasing it to wreak havoc on computer systems and other devices. They also design the attack phase, which can take different forms.
Some do it for the thrill of it to see how things blow up, others just want the bragging rights, while some are in it for the cold, hard cash they can get when you’re tricked into buying fake software, or sharing your personal information, which they use to steal your money.
How a Computer Virus Works
In the same way the flu infects and multiplies in your body’s immune system, a computer virus infiltrates your machine and its programs. Such malicious programs can be installed on your device without your consent or knowledge, and can inject malicious code that can manipulate and monitor your activity on the web.
Generally, a virus takes the following course when infecting your computer: the malicious application executes at the user’s request, and the virus code gets loaded into the computer’s CPU memory just before executing the legitimate code.
Once that happens, the virus begins to propagate by infecting your computer’s programs and applications and inserts malicious code as much as possible.
Depending on whether the virus resides in your computer or not, or it’s a boot sector virus, it can insert malicious code to programs as they open, executable files, or in the boot sector of the system disk such that it executes before your operating system loads fully.
At this point, it’ll execute the virus code, which its creator built it for, also known as payload. It then scans your computer’s hard drive for all sorts of things including your keystrokes, banking credentials, or turns your machine into a weapon for DDoS attacks against others. The attacker can use it to encrypt your data and demand ransom in exchange for restored access to your files and data.
During the pre-internet days, viruses spread via infected floppy or flash disks, but today, they can spread via the internet, or from computer to computer through virus code. They can also spread through email attachments, apps, or downloads from an infected repository.
Warning Signs That You Have a Virus on Your Computer
There are many different types of viruses categorized differently based on their behavior, which means some can fall into one or more categories. If you strongly feel your computer could have a virus but can’t quite tell whether it slipped past your security software’s defenses, here are some warning signs that tell you have a virus on your computer.
Slow Computer
If your computer is slow to boot or open programs, it’s likely that it’s infected with a virus. There are several factors that could affect your computer’s performance, but a virus is the most concerning because some types allow attackers to use its power for their own illegal purposes like mining crypto or carrying out a DDoS attack, all of which affect its performance.
Random Or Strange Fan Behavior
The fans in your computer help draw cool air while expelling warm air into the computer’s case, and kick into overdrive during resource-intensive tasks like gaming. However, if you notice strange behavior with the fans, it could be a sign of a virus infection, especially if the fans spin at maximum revs even when the computer is idle, or it gets abnormally hot.
Frequent Computer Crashes
This, coupled with the blue screen of death, could indicate the presence of a virus or problem with your computer. It’s not easy to pinpoint the exact cause as sometimes it could be due to overheating, driver problems, hardware issues or errors with the operating system.
Slow Internet Connection
This is often attributed to viruses and malware, which can hijack your connection and use your bandwidth for other activities. If you notice your connection is slow or there’s unusual high network activity, it could be that your computer has a virus. Sometimes you can lose your connection altogether.
Strange Browser Extensions You Didn’t Install
If you see new browser extensions that look strange, and that you don’t recall ever installing, your computer could be having a virus. Some extensions are legit and useful, but others can collect your personal data and sell it to a third party, or put your system at risk.
Browser Redirects
Redirects are common with virus infections, especially if you end up on sites you didn’t intend to visit. Such sites are usually laced with malware, and are used as dens for collecting personal information from unsuspecting users, or even encourage them to download more malicious software. Sometimes they’re used to drive traffic to such sites, in turn helping the cybercriminals make more money from ad impressions.
Increased Frequency Of Popup Ads Appearing On Your Screen
If you suddenly start seeing popup ads other than the usual frequency, or your browser’s homepage changes and the experience is slower, your computer could be infected with a virus. Some unwanted programs usually come with adware that leverages this opportunity to display unnecessary popup ads on get rich quick schemes, weight loss, and other phony virus warnings.
Irregular Social Media Account Behavior
This is another common sign that your computer has a virus, when your friends start receiving spam messages purportedly from you. They can get strange messages or comments from your account, which could be a sign that it has been compromised, or your computer is infected.
Security Software Won’t Run Or Doesn’t Work Properly
Your computer’s antivirus and security software helps protect it against the new malware that emerge by the day. However, some strains can disable it and stop it from running scans or updating, which is a telltale sign of viruses in your computer’s system.
If you notice the antivirus on your computer behaves differently from the norm, or you get warning messages about the system being unprotected, you could be dealing with a virus.
How to Remove Viruses From Your Computer and Prevent Future Infections
It’s not that easy to remove a virus from your computer, but you can use some or all of the solutions and measures listed below to cleanse your system and restore it to normalcy:
- Close unnecessary applications that consume resources and cause your fans to speed up. Check if they return to normal speed.
- Check for any notifications from Windows Defender Security as to whether your antivirus is disabled, and check for suggested solutions Restart your PC to re-enable your antivirus software as sometimes operating system and software updates can affect its functionality.
- Sign out from any compromised accounts on your computer and other devices
- Scan your computer for malware. If you have Windows Defender Security and it doesn’t flag files or programs with the virus, try using a variety of antivirus software as they each have their own virus signature databases. It’s also a good way of seeing what’s going on with better accuracy.
- Install an anti-phishing browser extension to stop dangerous sites from loading when you get redirected. Uninstall any such extensions that you didn’t install in the first place.
Other measures you can take to prevent future attacks include changing your passwords, enabling two-factor authentication, checking any of your downloads before they get into your system, and installing reliable security software plus a good ad blocker for a better browsing experience.
