Quick overview:
Every day, thousands of Windows users experience first-hand what an unprotected system means: phenomena such as Explorer.exe crashing, high CPU usage, unknown pop-ups, slow loading of websites, strange behavior of internal Windows tools, errors when accessing certain pages or unknown file operations are just a small list of the gigantic repertoire of errors that are reported daily in forums or on support hotlines. The experts know their Windows systems, check every possible source of error and at some point, when nothing else helps, the question is asked: Could it be that spyware, a virus, a worm or a Trojan is up to mischief? Even professionals swallow at this question, because permanent Internet visitors are far too seldom confronted with these issues - they themselves are not affected anyway. Experts encounter this kind of carelessness all the time and always recommend checking the system first.
Windows-Tweaks webmaster, Sandro Villinger, often receives such requests by e-mail and I don't know how many times I have helped people by recommending essential measures. Users suspect external sources of danger only recently, although this has become the number one source of errors in recent months. We will of course help you with our checklist (below). But first, we'd like to explain the dangers you face in your everyday PC life:
Computer viruses
Viruses are usually executable programs which, once they have entered the PC, gain almost complete control over it: The repertoire ranges from deleting/altering/damaging essential files to formatting the hard disk and making changes to the computer's basic control program (BIOS) - a virus can render a computer useless.
Trojan horse
These are smuggled into the system (e.g. via chat program, email, download, etc.) to gain control. Trojans open backdoors to the outside world so that hackers can gain unhindered access - they can then transmit sensitive data such as passwords, PINs and personal information to the outside world.
Worms
Come in via email and their attachments and can both destroy (viruses) and spy (Trojans). Optimum protection of the e-mail program should be a priority. There are also benign worms (e.g. a robot that indexes or analyzes and filters website content for search engines).
Spyware
Small programs that are usually installed via websites and send data about your surfing behavior to the manufacturer. Unfortunately, such software is often not programmed properly, so that errors can occur in Internet Explorer (or other Windows areas).
Dialer
These small programs connect to a provider of pornographic and/or illegal content via a 0190 number and rip off the unsuspecting user for several euros per minute for surfing pleasure.
And this is how you protect yourself...
Computer viruses: We generally recommend using at least two antivirus programs, so that deficiencies in detection rates in specific areas of one software are compensated for by the other. The following programs have proven themselves on the test computers:
1. Symantec Norton AntiVirus 2004: This user-friendly program finds most viruses and removes them reliably. You can download a time-limited version of NAV 2004 from this page. It is also able to ban many Trojans and worms from your PC.
2. Free-AV AntiVir Personal Edition: This free antivirus tool has proven itself to many users in the past because it delivers good detection rates (detects 70,000 viruses) and high-quality features. You can download it here.
3. F-Prot: The manufacturer FRISK has developed an interesting anti-virus and anti-Trojan program that is able to find not only 50,000 viruses but also very unknown forms of these malware.
4. AVG AntiVirus system: Both in the freeware and in the version 7.0, AVG offers professional protection against viruses.
5. McAfee OnlineScan: This free analysis checks the PC online for viruses.
6. McAfee VirusScan: The professional package from one of the most experienced antivirus developers in PC history.
7. avast! Home Edition: Another free virus scanner with an extensive guard function for P2P programs, mail applications and messengers.
Trojans: In addition to Norton AntiVirus, you should always take the following program recommendation to heart.
TrojanHunter: On this page you will find a time-limited version of TrojanHunter, which detects and removes most Trojans. A convenient update function keeps it constantly up to date.
Worms: The following program helps against the most common worms...
McAffee Stinger: This tool reliably removes the most common worms (myDoom, Lovesan etc.). Visit this page to download the program and stay up to date.
Spyware: Two of the best-known SpyWare tools are presented here...
Ad-Aware 6: Detects the latest SpyWares thanks to its integrated update function and removes them cleanly from your computer. You can get it here as freeware - the paid version offers network administrators in particular some interesting features.
SpyBot S&D: Also scans Windows very thoroughly for SpyWare and removes the affected parts of the system. As with Ad-Aware, traces are also covered, e.g. by removing cookies. Download!
BHO Demon: This monitors the settings of Internet Explorer and filters applications that use it to access the Internet. Download the BHO Demon here!
Dialer: To ensure that you, as a user of modem/ISDN devices, do not receive a heavy bill at the end of the month, we recommend the following applications. Note: It is also possible to have the 0190 number blocked by Telekom!
0190 Warner: This freeware warns of unauthorized use of the dial-up connection and saves the results in a log file. Users from Switzerland/Austria use the 0900-Warner (also available on this homepage), which works in the same way.
YAW (Yet Another Warner): This software is a useful dialer removal center and, thanks to updating the latest signatures, searches for all dialers in the Internet world.
This is what Windows-Tweaks also recommends...
Firewalls: So that you remain protected against many dangers (Trojans and hackers), it is not only the regular execution of the tools presented that helps, but also high-quality firewalls:
Symantec Norton Personal Firewall: Also on the Symantec download page you will find, in addition to NAV 2004, the trial version of the firewall, which is both easy to use and provides excellent protection against external attacks.
Kerio Personal Firewall: A free, very effective firewall, which also monitors traffic in front of and behind the firewall thanks to the intrusion system.
ZoneAlarm: One of the most frequently used firewalls for private workstations - has won countless awards in many PC magazines. Download here!
Outpost Firewall: More functions than ZoneAlarm, but more tailored to professional users: Outpost!
Sygate Personal Firewall: Very useful, very easy to use and very effective - both in the free version and in the Pro solution.
McAfee Personal Firewall Plus: The successful anti-virus software manufacturer is also launching a small, very positively rated firewall product.
Updates: In order for security gaps to be closed, you should do the following...
Update: Use the Microsoft Windows Update! An action that is strongly recommended by Windows-Tweaks.
Latest information on possible dangers: Microsoft often warns about current security patches and impending dangers on this page.
Program updates: Internet programs in particular (ICQ, file-sharing networks, etc.) are easy prey for hackers to gain access to the computer. The manufacturers are aware of the loopholes after some time, so you should generally check the manufacturer's website for updates and patches.
I hope that this page has helped you and I invite you to do another one: If you know of any very good security software (in any area) that you think is still missing from this page, please don't hesitate to write to me at: webmaster@windows-tweaks.info
NOTE FOR NEW PUBLICATION: This article was produced by Sandro Villinger and comes from the Windows Tweaks archive, which has been built up since the late 1990s.

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