PC Tune-up Glossary – Security and Performance Issues

Security and Performance Issues

The dangers of computer viruses are often discussed, but you may not be aware of other hazards that can jeopardize your privacy, damage your files, and cause frustrating downtime.

Fortunately, implementing some simple strategies can not only secure your computer and keep your data safe, but can make your computer work faster and more efficiently.

This document:

  • Reviews the risks for a computer with excessive clutter, speed and performance drains, insufficient security protection, and corrupted settings.
  • Suggests repairs and preventative measures that can both protect your computer and improve its speed, stability, and efficiency.
  • Provides definitions of key computer and security terms.


Risks posed by unneeded files

Every time you work on your computer or browse the Internet, temporary files, cache files, and cookies are saved to your hard drive. Most of these are files that you will never use and do not need to save. More unneeded buildup occurs from deleted files accumulating in the Recycle Bin. All this debris clutters your computer and overtaxes its resources.



  • Reduction in processing. Unneeded files consume memory and take up drive space. Instead of focusing on processing the services you really need, your computer is using resources to process useless items.
  • Recurrent crashes and lock-ups. A glut of unnecessary files increases drive fragmentation, which burdens the hard drive. With an excessive amount of debris, Windows can start to behave in unusual ways, including locking up or crashing.
  • Endangered privacy. Anyone who has access to your computer can see the Web sites you have visited and easily open files you have deleted.



  • Erase temporary files. Simply deleting files from your Web browser cache or temporary directories does not completely erase these tracks. Most security advisers recommend using software that can thoroughly clean out cookies, temporary Internet files, and cache files.
  • Empty the Recycle Bin. Windows stores deleted items in the Recycle Bin for easy recovery, and as you work on your computer, these deleted files quickly accumulate. Periodically empty the Recycle Bin to reclaim valuable hard drive space. Note: Items left in the Recycle Bin also pose a privacy risk because these files can be easily retrieved. Where confidentiality is critical, not only empty the Recycle Bin, but also use a data wiping program to thoroughly obliterate data.
  • Remove unneeded files and programs. Occasionally review the data you have saved and installed. Delete the documents and files you no longer want and uninstall programs you are no longer using. Consider archiving rarely used files to a CD or other removable media.

Risks posed by speed and performance drains

Various inefficiencies can bring your computer’s processing to a crawl, including fragmented hard drives, splintered system memory, scattered registry entries, and unneeded programs starting with Windows.



  • Slow boot times. Various programs and services are set to load when Windows loads. Some of these programs, such as antivirus protection, are desired, but many are useless and needlessly slowing the time it takes to start your computer.
  • Reduction in processing. When hard drives and system memory become fragmented, computer performance is significantly slowed. Files take longer to open and programs take longer to start.
  • System and file damage. Highly fragmented files are more prone to becoming corrupt. A highly fragmented hard drive places more strain on the heads, which in severe cases can lead to a head crash and a loss of data.
  • Exposure to infections. Trojans (malicious software) might also be loading at startup. Trojans are usually designed to load when you restart your computer.



  • Defragment your hard drive and system memory. Defragmenting your hard drives reorganizes scattered data, which boosts file access speed and extends the life of the drive. Defragmenting system memory reclaims valuable memory and improves PC efficiency and speed.
  • Compact the registry. Compacting the registry reorganizes entries, which maximizes free space and improves the efficiency and speed of registry processing.
  • Remove unneeded services from startup. Eliminate startup items that are unnecessary. Removing these unneeded performance drains will boost your PC’s speed, particularly the time it takes to boot, and will eliminate potentially dangerous programs.

Risks posed by malicious software

Computer viruses, hackers, and other Internet dangers continue to pose a high risk. A range of malicious programs (viruses, worms, Trojans, etc.) are designed to damage computers or obtain confidential information from them. These infections can wreak havoc by causing permanent computer damage, destroying data, and enabling identity theft.



  • Reduction in processing. Infections can cripple a system and bring processing to a halt. Viruses can make dangerous changes to the vital registry, causing system slowdowns and crashes.
  • Lost files. Your files – treasured photos, valuable music, important financial records – can all be destroyed if your computer becomes infected.
  • System and file damage. Viruses are designed to alter the operation of a computer. In addition to damaging files, viruses can harm your registry, your operating system, and even your hardware.
  • Data and identity theft. Trojans can enable the theft of any data saved on your computer, including banking and credit card information, passwords, address books, and other private information.
  • Financial risk. The monetary cost of recovering from data loss or identity theft can be devastating.
  • Spreading of infections to others. You can unknowingly spread viral infections to your friends, family, and business associates just by sending an email or leaving your computer unattended. Hackers can secretly take control of your PC and use it to attack and infect other computers.



  • Use a firewall. A firewall is vital to secure Internet activity. A firewall puts up a barrier against hackers and other intruders, but allows the Internet access that you do want. Configure the firewall so that only the programs and Web sites you trust are allowed to pass through.
  • Use antivirus software. Antivirus software is a must-have for anyone who uses the Internet. This software blocks computer infections and detects and removes any existing infections. Make sure you keep the virus signatures up to date for continual protection.
  • Patch known security flaws. Many malicious programs exploit known security vulnerabilities in operating systems and browsers. Install the latest security patches, or use a specialized program that can automatically repair these flaws.
  • Only download trusted programs. Only download programs from trusted Web sites or refer to a trusted source for information. Do not install software if you are not sure about it.
  • Back up important files, including the registry. Establish and follow a schedule for regular backups of your data. Ideally, use a backup program that backs up all files, including programs and hidden operating system files. Regular backups of the registry are also recommended to protect its critical settings.
  • Permanently erase deleted confidential data. A file deleted through Windows is not completely erased; even though you can’t see the file, someone using easily available tools can recover it and view its contents. For highly confidential data you have deleted, use data wiping software that completely erases all data remnants.

Risks posed by corrupted settings

Over time and with regular usage, a computer can slowly degrade and become unstable, with frequent crashes, perplexing error messages, and a host of other unexpected nuisances. Some defects that can crop up over time are invalid registry references, broken shortcuts, hidden spyware, obsolete uninstallation files, and physical errors on the hard drive and other devices.



  • Reduction in processing. Unneeded uninstallers and other invalid data in the registry overburden Windows processing. Spyware wastes system memory and can slow or stop Internet processing and lead to overall sluggish performance.
  • Recurrent crashes and lock-ups. Damaged hard drives, spyware parasites, obsolete shortcuts, and inaccurate registry references frequently cause computer crashes and lock-ups. A volatile computer is extremely frustrating and can become practically unusable.
  • Exposure to infections. In addition to burdening system memory, spyware has been used to deliver Trojans and viruses. Any program designed to install on a computer without the user’s knowledge carries a potential security risk.
  • System and file damage. Damaged sectors on a drive can prevent files from being accessed or saved and can cause system crashes. Spyware often incorporates poorly or carelessly designed functions that can harm your computer’s operating system and cause conflicts with your valid software.



  • Use spyware removal software. Spyware is created with covert techniques that make it difficult for people to spot. The safest approach is to use software that scans for and deletes spyware. Note: Do your research when dealing with unknown vendors. Some spyware removers advertised as “free” are actually spyware themselves, or contain Trojans and viruses.
  • Repair hard drive errors. A damaged hard drive can prevent you from saving files and retrieving existing files. Using software to fix hard drive errors protects your data and improves PC stability.
  • Repair registry errors. The registry is vital to your computer’s ability to run correctly and when it becomes corrupted, overall degraded performance occurs. Most technical advisors recommend that specialized software be used to make registry changes, rather than making manual changes.
  • Be cautious of so-called “free” programs. Free programs, such as file-sharing software, screen savers, and games, are regularly bundled with spyware. Disclosure of spyware is often hidden in the fine print of a license agreement. Be sure you understand what is packaged with a program before you download it.


Adware is software that generates advertisements, usually as banner ads or pop-up windows. Adware is usually bundled with other software and installed without your knowledge. While usually not physically damaging or outright malicious, the intrusive behavior of adware can be annoying and waste system resources.

cache file

Cache files are used to store information on a temporary basis for quick access. A common example of a cache file is a browser cache. Every time you open a Web page, your browser creates a cache file (a temporary copy) of the page’s text and graphics. When you open the page again, your browser checks the Web site server for changes. If the page hasn’t changed, your browser loads the page from cache on your hard drive, which is much faster than originally loading it from the remote server.


A cookie is a small text file that some Web sites save to your local, hard drive while you are browsing the site. Cookies contain identifying information, such as log in and shopping cart information. Cookies are useful for loading Web site preferences and login settings, but they can also contain information that can be passed to others without your knowledge, usually for advertising purposes.


Over time, as you create, delete, and download files, your computer cannot store data as one unit and instead will split it up and store pieces in various drive locations. A fragmented hard drive has a large amount of such scattered data and can significantly slow PC performance. Similar to hard drives and other storage media, system memory can also become fragmented with time and usage.

Defragmenting reorganizes data so that components are stored closer to each other. Regularly defragmenting hard drives and system memory improves drive speed, reclaims valuable memory, and extends the life of your computer.


Malware (MALicious softWARE) is a generic term covering a range of software programs that are designed to damage computers or to obtain unauthorized information from computers. Some specific types of malware include viruses, worms, and Trojans.


The registry is a database that holds configuration settings used by your Windows operating system. The registry is vital to your computer’s ability to run correctly. It stores key data that Windows requires and continually references, such as user profiles and settings for installed software and hardware.

Only manually edit the registry if you know what you are doing; making inaccurate modifications can severely damage your computer. Always back up the registry prior to making any changes.


Spyware is tracking software that is installed on your computer without your notice or consent. It sends information about your computing activities back to its source, usually for advertising purposes, but sometimes for much more dangerous purposes such as identity theft or credit card fraud.

The effect of spyware varies depending on what its creator’s intentions are and can include consumption of valuable system resources, random lockups, crashes, or slowdowns; Web browser Home page or search page redirection; unwanted software installation; and random or incessant pop-up ads.


A Trojan, or Trojan horse, is a software program that appears to be desirable or useful, but intentionally does something you do not expect. The effects of Trojans can range from simply displaying pop-up ads to destroying files or enabling the theft of data.

Trojans are distributed in executable files, such as through email attachments, CDs, and Internet downloads. People can be lured into installing a Trojan because it appears that it will serve a legitimate purpose. Unlike viruses and worms, a Trojan is not designed to make automatic copies of itself. However, Trojans can carry viruses and other malicious software within them.

Two specific types of Trojans are keyloggers and RATs:

  • A keylogger, or keystroke logger, captures all keystrokes and then records that information to a log file. With a keylogger, a hacker can capture your logins, passwords, credit card numbers, and any other confidential information that you type. Once collected, this information can be silently transmitted to the Trojan’s creator for malicious purposes, such as credit card or bank fraud.
  • A remote access Trojan (RAT) gives someone remote access to and control of a computer. With a RAT, imposters can send email messages that will appear to be from you; read, modify, or destroy your documents; and use your PC to attack and infect other computers.


A computer virus is a software program designed to alter the operation of a computer. Most viruses are malicious and intended to cause damage, but even a benign virus can harm a system. Viruses can damage files, software programs, the registry, and hardware.

Viruses are distributed in executable files, such as through email attachments, CDs, and Internet downloads. A virus infection occurs when the infected file is run. A virus also automatically replicates, or makes copies of itself, by secretly embedding its programming code into other programs.

The term “virus” is often used as a generic, collective reference that includes other types of malicious programs, such as worms and Trojans.


A computer worm is a software program designed to reproduce and spread among computers. Most worms are malicious and intended to overwhelm system memory or network bandwidth. Worms can crash an entire network of computers or an individual computer.

Worms are generally distributed in email attachments or through unprotected Internet activity. A worm spreads very rapidly because it is self-contained. It replicates itself and, unlike viruses, a worm does not need to infect another program to spread.

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The Whole Home License® is iolo’s licensing policy that allows you to install and keep your software running on all of your compatible devices within the same home. Previously, users were allowed to install and license their iolo software simultaneously on a maximum of three PCs. Under the Whole Home License, a single activation key allows you to use your iolo software on all of your PCs, other than any PCs you use for business purposes. What you need to know about Whole Home Licensing

  • You, your spouse, and your relatives living within the same household may use the same license on any number of PCs that you own which are not used for business.
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You can view the Activation Key on the original computer from within System Mechanic > red menu bar > key icon > Activation Key.