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Showing posts from June, 2012

A+: Where to Go for More Information

After you’ve gathered as much information as possible, you might find that you still need more help. User manuals for components often are discarded, software drivers need to be updated, and some conflicts don’t have easy answers. Use the following resources for more help: •  Manufacturers’ websites—  Most system and component manufacturers provide extensive technical information via the World Wide Web. You’ll want to have the Adobe Reader program in its latest version available to be able to read the technical manuals you can download (Adobe Reader itself is a free download from  www.adobe.com ). These sites often contain expert systems for troubleshooting, specialized newsgroups, downloadable driver updates, and other helps for problems. •  Printed manuals—  Although many vendors have switched to web-based or Adobe Reader (PDF) manuals, some vendors still provided printed manuals or quick-reference diagrams. Be sure to file these in a way that permits quick access when neede

A+: Best Sources for Replacement Parts, and Keeping Track of Solutions

“Known-Working” Doesn’t Mean “New” To perform parts exchanges for troubleshooting, you need replacement parts. If you don’t have spare parts, it’s very tempting to go to the computer store and buy some new components. Instead, take a spare system that’s similar to the “sick” computer, make sure that it works, and then use it for parts. Why? Just because it’s new doesn’t mean it works. I once replaced the air conditioning compressor on my van with a brand-new, lifetime-warranty alternator that failed in less than a week, and six more replacements failed (all from the same batch or defective parts). Whether it’s a cable, a video card, a monitor, or some other component, try using a known-working item as a temporary replacement rather than brand-new. Rather than give away, sell, or discard working video cards, hard disks, and other components you have replaced with faster, bigger, better upgrades, keep at least one of each item to use as a replacement for testing purpo

A+: Points of Failure on the Outside of the Computer

The front of the computer might provide valuable clues if you’re having problems with a system. In case of problems, check the following common points of failure for help. • Can’t read CD or DVD media— The drive door on the CD-ROM or other optical drive might not be completely closed or the media might be inserted upside down; press the eject button to open the drive, remove any obstacles, reseat the media, and close the drive. You can also eject optical media with Windows Explorer/My Computer. Right-click the drive and select Eject . If the drive doesn’t eject the media, there could be a problem with the drive’s data cable, cable connection, or power connection. • Can’t shut down the computer with the case power switch— The case power switch is connected to the motherboard on ATX, BTX, and other modern desktop systems, not directly to the power supply as with older designs. The wire might be loose or connected to the wrong pins on the motherboard. Keep in mi

A+: What Components to Check First

As the previous subsystem list indicated, there’s no shortage of places to start in virtually any subsystem. What’s the best way to  decide whether a hardware, software, or firmware problem is the  most likely cause? Typically, hardware problems come and go, whereas software and firmware problems are consistent. Why? A hardware problem is often the result of a damaged or loose wire or connection; when the connection is closed, the component works, but when the connection opens, the component fails. On the other hand, a software or firmware problem will cause a failure under the same circumstances every time. Another rule of thumb that’s useful is to consider the least expensive, easiest-to-replace item first. In most cases, the power or data cable connected to a subsystem is the first place to look for problems. Whether the cable is internal or external, it is almost always the least-expensive part of the subsystem, can easily come loose, and can easily be damaged. If a c

A+: Thorough Troubleshooting *

Virtually every subsystem in the computer has hardware, software, and firmware components. A thorough troubleshooting process will take into account both the subsystem and all of its components. The following steps are involved in the troubleshooting cycle: Step 1. Back up customer data (if possible). Before you do anything to a customer’s system, you should ensure that the system’s data has been backed up. The easiest way to ensure that you can restore the system to its “as-was” configuration is to use a disk-imaging program such as Symantec Norton Ghost or Acronis True Image. The current versions of these programs perform disk-imaging to preserve the contents of the system drive (and other specified drives) at both a data and operating system level. However, if you need to restore specified files only, the current versions of these programs also permit file-level restoration. For speed and convenience, use an external hard disk connected to a USB 2.0, FireWire, or

A+: Is a Problem Is Caused by Hardware or Software

The oldest dilemma for any computer technician is determining whether a problem is caused by hardware or software. The widespread use of Windows operating systems makes this problem even more acute than it was when MS-DOS was the predominant standard, because all hardware in a Windows system is controlled by Windows device drivers. A troubleshooting cycle is a method that you can use to determine exactly what part of a complex system, such as a computer, is causing the problem. The troubleshooting cycle used in this section goes into more depth than the CompTIA six-step troubleshooting process. The first step is to determine the most likely source of the problem. The client interview will help you determine which subsystem is the best place to start solving the problem. In the previous example, the printing subsystem was the most likely place to start. A  subsystem  is the combination of components designed to do a  particular task, and it can include hardware, software, and firmwa

A+: Recording Symptoms and Error Codes

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If tests rule out power and interference, proceed to tests focusing on the hardware or software that appears the most likely cause of the problem. Which test or diagnostic routine is the best one to start with? Before you perform any specific tests, review the clues you gathered from the client. Examples of places where symptoms and error codes can be found include • Event Viewer— The System log records error information regarding drivers and system files, while the Application log records information and errors about applications within the operating system. • Device Manager— If a device in Device Manager is disabled it will be marked with a red x (Windows XP) or a down arrow (Windows Vista); if it is not configured properly there will be an exclamation point against a yellow background (Windows XP and Vista). Device Manager also displays codes in the Properties window of a device indicating particular issues. • On screen messages— Various messages can

Defragmentation explained - hard drive si, SSD no

http://arstechnica.com/information-technology/2012/06/inside-the-ssd-revolution-mobile-devices-and-modern-oss/  is an excellent  explanation of defragmentation of hard drives, and why you shouldn't do it with solid-state drives (SSDs).

A+: How to Evaluate the Client’s Environment

Depending on the clues you receive in the initial interview, you should go to the client’s work area prepared to perform a variety of tests. You might need to perform several tests to rule out certain problems, and must look for three major issues when evaluating the customer’s environment, and      • Power issues     • Interference sources     • Symptoms and error codes—this might require that you try to reproduce the error TEST ........... REQUIRES Power .......... Multimeter, circuit tester BIOS beep, error codes ... List of BIOS codes, POST card/display device Printer self-test ........ Printer, paper Windows bootlog .......... Start Windows w/ Bootlog option on I/O port ....... Connect loopback plugs, run 3d party diagnostcs Video tests .......... Third-party diagnostics Hardware resources ........... Windows Device Manager Device drivers ........... Windows Device Manager Testing Power Systems that won’t start or that have lockups or shutdowns with no error

A+: Client Interviews

The client interview is the all-important first step in solving any computer troubleshooting situation. During the client interview, you need to ask questions to determine the following information: • What hardware or software appears to have a problem?— The user might have an opinion about this, but don’t be unduly swayed by a statement such as “the printer’s broken”; the device or software the user believes to be at fault might simply reflect a problem coming from another source. • What other hardware or software was in use at the time of the problem?— The user probably will answer these types of questions in terms of open applications, but you will also want to look at the taskbar and system tray in Windows for other programs or routines that are running. Pressing Ctrl+Alt+Del will bring up a task list in Windows that has the most complete information about programs and subroutines in memory. To determine the exact version of a Windows-based program in use,

A+: Troubleshooting and a six-step process

Two factors make for successful troubleshooting: extensive computer knowledge and an understanding of human psychology. You must understand how hardware and software work to troubleshoot them. You also must treat customers with respect. By combining these two factors, you can quickly detect and solve computer problems. To become a successful troubleshooter, you need to     • Learn as much as possible during the client interview     • Evaluate the client’s environment     • Use testing and reporting software to gather information about the system     • Form a hypothesis (a theory you will try to prove or disprove)     • Use the troubleshooting cycle and the CompTIA six-step troubleshooting process to isolate and solve the problem, to wit: 1 Identify the problem 2 Establish a theory of probable cause (and question the obvious) 3 Test the theory to determine the cause 4 Establish a plan of action to resolve the problem and implement the solution 5 Verify full system function

A+: Hazards

Computers and their peripherals can kill or injure you if you don’t take reasonable precautions. Here we discuss computer maintenance and the precautions you can take against these dangers. Computer equipment and supplies can pose a number of potential hazards for the technician (and, in some cases, for computer users):     • High voltage sources, such as computers, and peripherals, such as printers and monitors     • Mechanical devices, such as printer mechanisms     • Power or data cables running across floors or other locations where users could trip and fall     • Liquids, such as those used for cleaning or refilling inkjet cartridges     • Situational hazards, such as unsafe temporary equipment or cabling locations     • Atmospheric hazards, such as those created by the use of toxic cleaners or the discharge of computer-room-rated fire suppression chemicals     • Moving heavy equipment, such as laser printers, servers, large UPS systems, or print/scan/copy devices.

A+: More ESD Precautions

Caution!: All work mats and wrist straps should have a 1-megohm resistor, to stop any high voltage that comes through the ground line from injuring you! Correct equipment storage should have two goals: Eliminating the possibility of ESD, and protecting equipment from impact damage. To protect equipment from ESD, store equipment in the Faraday cage antistatic bags originally supplied with the equipment; retain bags for installed equipment for reuse. Faraday cage antistatic bags feature a thin metallic layer on the outside of the bag, which is conductive and prevents ESD from penetrating to the components inside. Thus, metalized metallic bags should never be used for temporary mats for components; if you lay a component on the outside of the bag, you’re laying it onto a conductive surface. Colored antistatic bubble wraps also work well for parts storage and can also be used as a temporary mat, too. If you use bubble wrap, make sure it is antistatic. Store components in approp

A+: Protect Yourself!

You can best equalize the electrical potential of a computer or component that is being serviced by placing the computer or component on an antistatic work mat equipped with a wrist strap; attach your wrist strap to the mat. This will help place you and the component at the same level of electrical potential, and thus eliminate the “need” for ESD to occur to equalize the potential. Caution:  You should use a commercial wrist strap for most types of computer service, but there is one major exception: Never ground yourself when you are working with high-current devices, such as when you discharge a CRT monitor. Grounding yourself to such devices could cause your body to receive a fatal high-current electrical charge. For additional safety, use the alligator clip on the antistatic mat to attach to the component or computer you are working on. Attach the clip to unpainted metal on the chassis, such as the frame. This provides superior equalization for the mat, you, and the hardware

A+: Safety - MSDS (Material Safety Data Sheet) and ESD (Electronstatic Discharge)

What happens if a toddler decides to taste the ink in a printer cartridge? The Material Safety Data Sheet (MSDS) knows. Many consumable products such as cleaners and printer cartridges have an MSDS. In more and more cases today, this information is available from the manufacturer’s website on the Internet. The MSDS can be used to • Determine safe storage practice • Determine treatment if the product is accidentally swallowed or contacts the skin • Determine safe disposal methods • Determine how to deal with spills, fire, and other hazards Anyone who works with electronics, especially disassembled components, needs to be very concerned about ESD. ESD is the static electricity discharge that happens when two differently charged objects (such as your body and a computer component) come in contact with each other. ESD is an invisible killer of memory modules, interface cards, hard disks, and other computer components, because ESD buildup and discharge happens long

A+: Disposal of Obsolete Hardware

If you send your obsolete PC, printer, or monitor to a landfill, it will have plenty of company. Millions of old units go there every year; it’s legal (except for monitors which contain lead or mercury ), but it’s also a waste of equipment that could teach somebody something or still be useful to someone. Here are some better ways to deal with obsolete computers and peripherals: • If possible, try to dispose of your working, cast-off computer equipment by giving it to a school, charity or especially a computer rebuilding society such as Freegeek.org . These organizations might be able to wring additional years of useful life out of the equipment and are usually grateful for the opportunity. • To dispose of non-working equipment, see if an electronics trade school is willing to take the equipment for classroom use. Some electronic and computer service facilities will allow you to drop off defective monitors with payment of a small disposal fee. • Use “computer” a

A+: Recycling Batteries, Solvent and Toner

Nothing lasts forever in the computer business. Whether it is a worn out real-time clock battery, an obsolete monitor, or an empty toner cartridge, there’s a right way to get rid of it or to recycle it. Generally, the more “durable” a computer-related item is, the more likely it is that it should be recycled when it reaches the end of its useful life, instead of simply being discarded. Recycling is important and can have legal ramifications for a company. In this section you learn the proper way to recycle toner cartridges and batteries and how to dispose of chemical solvents, monitors, and other computer hardware. When dealing with computers, power, networking, and anything else in IT, remember to put safety on the top of your priority list. Computer equipment is not a toy and should be treated with care. Another issue to consider is how you dispose of your technology, since this will affect the environment. Most companies have procedures in place that specify what to do with comput

A+: Network and Internet Troubleshooting

Can’t Access Network Resources   If an error message such as Duplicate Computer Name or Duplicate IP Address is displayed during system startup, open the Network icon and change the name of the computer or the system’s IP address. Contact the network administrator for the correct name or IP address settings to use. Significant Drops in Network Performance   Significant drops in network performance can be traced to a variety of causes, including • Damage to cables, connectors, hubs, and switches • Expanding network capacity with hubs in place of switches • Connecting high-speed NICs to low-speed hubs or switches • RFI/EMI Interference with Wireless Networks If network usage patterns remain constant but some users report lower performance, check cables, connectors, and other network hardware for physical damage. Dry, brittle, and cracked cables and connectors can generate interference, which forces network stations to retransmit data because it was

A+: Network Command-Line Tools

Windows contains several command-line tools for troubleshooting and configuring the network. These include the following:     • Net— Displays and uses network resources     • Ping— Tests TCP/IP and Internet connections     • Tracert— Traces the route between a specified website or IP address and your PC     • NSLookup— Displays detailed information about DNS     • IPConfig— Displays detailed TCP/IP configuration about your Windows NT/2000/XP system Using the Net Command Windows includes the Net command for use in displaying and using network resources from the command line. Some of the Net commands you can use include     • Net Help—Displays help for a Net option; for example, use Net Help View for help with the Net View command.     • Net Use—Maps a network drive to a shared resource on the network; for example, Net Use Q: \\Tiger1\shared. In this example, Q: will behave just like any other drive letter such as C:, D:, and so on. The only difference is that it will redir

A+: Browsing and Security

You can configure Internet Explorer’s default security settings for Java, ActiveX, and other potentially harmful content through the Internet Options’ Security tab. Open the Internet Options tab with Control Panel, or click Tools, Settings, Internet Options within Internet Explorer. Depending on the version of Internet Explorer there will be five or four default security settings: High, Medium-high, Medium, Medium-Low, and Low. High blocks almost all active content and prevents websites from setting cookies (small text files that can track website usage). Medium (the default) enables some active content but blocks unsigned ActiveX controls. Medium-low blocks unsafe content but downloads other content without prompts, and low has no safeguards. Each setting is matched to a web content zone. By default, all sites not in other zones are placed in the Internet zone, which uses Medium-high security (Medium on older versions of Internet Explorer). The local Intranet zone uses Medium-low

A+: Browser and Script Setup *

A web browser, such as Microsoft Internet Explorer or Mozilla Firefox, is the main interface through which you navigate the Internet. Internet Explorer is a standard component of Windows. Updates and newer versions can be downloaded manually from the Microsoft website or via Windows Update. Other browsers can be downloaded in compressed form and installed manually. Depending on how you connect with the Internet, you might need to adjust the browser configuration. Typical options you might need to change include • Proxies for use with LAN-based or filtered access— Users who access the Internet through a local area network might be doing so through a proxy server. A proxy server receives a copy of the website or content the user wants to look at and checks it for viruses or unapproved content before passing it on. The proxy server information is set through the browser’s configuration menu (for example, Internet Options in Internet Explorer). • Automatic dial up fo