The term "malware" (malicious software) is a general term used to describe a multitude of bad software that is created with the intention of harming your computer, your privacy, and your security. This incudes viruses, spyware, adware, pop-ups, and other forms of advertising and information mining. These programs use a variety of shady techniques and security vulnerabilities to make themselves difficult to remove. Once infected, a piece of malware can change anything it wants on your system. This includes changing security settings that could make it easier for you to get more. It can also severely slow your system and/or internet connection down, and in some cases even break your connection when you attempt to remove them.
Viruses, Trojans, and Backoors
Viruses are programs written to propagate themselves to as many computers as possible. Viruses spread through e-mail, file downloads on Peer to Peer (P2P) networks such as KaZaa, network shares, and exploits in security vulnerabilities. Their intentions vary, but viruses can be harmful in many different ways. Sometimes they choke internet connections worldwide with their traffic, which can affect your internet service, your e-mail, or your web site if you have one. Some cause your computer to restart over and over again. For example if you install Windows XP on a new computer and hook it up to the internet without the proper precautions, there is a good chance you will be infected by the Blaster worm within seconds. Viruses can also use your infected computer as a zombie machine along with all the other infected machines to attack certain web sites. This is known as a Distributed Denial of Service (DDoS) attack. For example, a virus could exploit a security weakness in Windows, and then use the infected machines to attack the Windows Update site in order to make it more difficult for users to patch their machines. Viruses can do whatever they want once they are on your computer, so it is very important to deal with them.
Trojans are similar to viruses, but usually come in a package that looks safe. They also do not replicate. Backdoors are programs that are often installed like viruses or trojans, and run silently in the background. They allow an attacker to remotely control your computer. This includes seeing what is on your screen (credit card numbers, private conversations, passwords), uploading files, executing programs, changing passwords, etc. Many viruses and trojans contain a backdoor component as well.
Spyware/Adware
Spyware and Adware are both very similar, and many of the programs are both. Spyware is used to mine information from your system or track where you go, for marketing purposes. Adware is software that runs on your computer and shows you advertisements, usually in the form of pop-ups. These programs come in a variety of forms and are acquired in a variety of ways. Many of them also hijack your browser's start and search pages, so that when you start your browser, the first page you see is their advertising cesspool, or when you try to search for a web site, or mis-type a URL you end up once again at their web site.
Many of these programs come from web pages. A window will come up asking if it's okay to install such-and-such program, and an unsuspecting user clicks yes thinking it is required for the web page to function. Or a user may accidentally click yes. Some keep asking over and over if you say no until you finally say yes just to get it to go away. A lot of these programs also come bundled with legitimate software as a way to fund it. If you've ever downloaded something that included GAIN, you no doubt are inundated with ads. Some examples are KaZaa and the free version of DivX. The software that comes bundled with these advertising programs is usually not worth it. More often than not, there are ad-free alternatives available that are usually better in other ways as well.
Browser toolbars are another favorite for adware developers. These sit at the top of your browser, as a search bar, acting like they're useful. The truth is they are there to spew ads at you. They usually become installed as described above (a window asking you to install them). One of the most infamous is CoolWebSearch, which has many variants and is extremely hard to get rid of. It is often treated as a trojan. Not all search bars are malicious, however. The toolbars by Google and Yahoo! for example are not harmful.
Some adware is willingly installed by users. If you're using your computer right now with pretty cursors provided by CometCursor and weather information provided by WeatherBug, then you fall into this category because those are both notorious adware programs. They aren't the only two though. Once again, better ad-free alternatives are usually available for these programs.
Pop-Up/Pop-Under Advertisements
This section is included to clear up a misconception about the origin of the many pop-ups people receive. Most people think of pop-up ads as coming from web pages because this is where they were originally used the most. They are still used on web pages. However, most of the problems people have with pop-up ads today come from spyware and adware as described above. These pop-up ads are usually not blocked by so called "pop-up blockers" and are not coming from the web page you are looking at. Pop-up ads that come from web pages are usually not dangerous, just annoying. Sometimes they try to install adware from a pop-up, and that is dangerous, but most are just annoying. A pop-up blocker will help with these, and there are many available for free (but be careful because some are adware)!
Removal: Getting Rid of the Bad Software
There is a lot of software out there claiming to remove malware. Virus scanners, adware clean-up utilities, etc. A virus scanner is a good thing to have, but only if you keep it updated. We can scan your computer for the latest viruses using a variety of software, and even install a free virus scanner. Be careful if you go searching for malware removal utilites. There are a bunch that are actually malware themselves. There are a few really good malware removal utilities out there, however. We use several of them ourselves. One isn't really enough. Most of them miss a little something here and there that another utility can pick up. You can run these yourself, and generally get good results.
However, while we use many of these utilities ourselves, we can also remove new and unknown malware manually. Sometimes a new variant of these programs come out, or a new one entirely, and it can't be removed completely by using the automated tools. We can handle this. By having us scan, you're also letting an experienced professional who's very familiar with the tools run them. It can be easy to inadvertantly remove things you might need or want; things are that perfectly legitimate. It's also easy to break your internet connection by removing certain malware incorrectly. We can prevent or fix this.
Once the offending programs are removed, how do you keep them from coming back? Once again this is an area in which we excel! We can set your computer up so that it is very difficult for these programs to use the usual techniques. We can install a virus scanner for you, malware detection tools, pop-up blockers, etc. We'll show you what to look for, and how to avoid common pitfalls.