Operating System Troubleshooting – CompTIA A+ 220-902 – 4.1

Problems with your operating system usually effect the overall operation of your computer. In this video, you’ll learn how to identify and troubleshoot some of the most common operating system issues.

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Nothing can bring your day to a grinding halt better than a blue screen of death. Your system comes to an immediate halt, and usually see a blue screen, or some other error message on the screen. If this is happening when you’re starting up your system, or shutting it down, it might be related to bad hardware.

You might have bad drivers, or there might be an application causing a problem with all of these. If you’re running in Mac OS, you might be getting the Apple pinwheel, or the spinning beach ball. In those cases, it may be that an application is trying to access a resource that’s unavailable, or there may be resource contention with multiple applications trying to access it simultaneously.

In Windows, you could try rolling back to a previous configuration with the last known good setting. You could also choose a System Restore to a previous point in time. Or you can choose the specific driver that you think might be causing the problem, and roll back to a different version of that driver.

You can do many of these using Safe Mode to try to avoid some of the startup problems you’re having with the blue screen of death. If you think the problem might be related to hardware, it might be worthwhile to open the cover and try re-seating all of the components, and all of the cables on the inside of your computer. You also might want to try running some hardware diagnostics.

The manufacturer might be able to provide you with hardware diagnostics, or they might be already built into the BIOS of your computer. If you start your computer, and you get a very abrupt “can’t find the operating system” or “operating system missing”, then you have a bigger problem on your hands.

This could also occur because you’ve installed an additional operating system, and you’ve overwritten the original boot loader that was configured on your computer. And now no boot loader is installed, and no operating system can be found. This might also occur because you’ve left some media in a boot drive, so make sure you don’t have any type of optical media or USP storage device connected to your computer, and try rebooting again.

In Windows, you could also run a startup repair. This is going to not only identify where your operating system is, you can also resolve any problems with your boot loader if you think the problem might be related to the boot configuration database or the BCD in your Windows system.

Then, you can always repair this yourself from the command prompt of your operating system. I’ll remind you later in this video how you get to this command prompt, but once you’re here, you can run the command bootrec/rebuildbcd to rebuild the boot configuration database.

If you start up your computer, and you get this screen, the Windows error recovery screen, it will tell you that Windows did not shut down successfully. If you think you know why Windows did not shut down successfully, then you may simply want to choose Start Windows normally , and continue with this process.

If this is something that is occurring often, and you aren’t quite certain why this might be happening, it might make more sense to launch startup repair, and fix whatever issue might be involved with this particular problem. You can also run this by pressing F8 when the system starts, or simply choose launch startup repair whenever the Windows error recovery screen is shown.

If you start your computer, and you’re not getting any type of graphical user interface, you’re not seeing a log on dialog box, you might not be getting any screen at all– and you probably have some type of driver corruption, or some problem with files that are part of the operating system. One of the things you can try, is to start in a mode while Windows is booting, you can press the F8 key, and choose to start in a mode.

Once the system is started, you might want to try running SFC, this is the System File Checker, that will check all of your operating system files, and make sure that they’re all working properly. This is something you can usually run from the recovery console at the command prompt. You might also want to consider updating your drivers. You can do this in Safe Mode, especially if your problem happens to be with a video driver that’s causing the screen to go black when you try to start your system.

If you’re Windows 8, or 8.1, you might also try running a repair, or refresh. And you could, of course, also recover from backup, regardless of what operating system you’re using. Startup repair is a Windows utility that can solve a number of problems. If you start your computer, and you get a message that says, missing NT loader, that means that the main boot loader in Windows is missing.

This is usually because you have a removable storage device, like an optical drive, or USP drive, connected, and it’s trying to boot from those devices, rather than your main storage device. You can run Startup Repair to automatically fix these files, or you can replace the files manually and restart your system.

Another good reason to Startup Repair might be because you’re getting a message that says “Missing operating system”. This is often because your boot configuration data, or BCD, might be incorrect. You can of course run Startup repair to automatically repair the BCD, or you can manually configure the BCD yourself.

And if your system is constantly starting up in Safe Mode, instead of starting in the normal Windows mode, then you absolutely want to run Startup Repair to try to resolve what issue may be preventing Windows from starting normally. To get to the Windows Startup Repair, you need to get to the advanced boot options.

You get to those by pressing F8 before Windows loads. If you have a boot manager, like I do, you can press F8 while boot manager is shown, or simply press F8 before the Windows logo appears. When you press a F8, you get the advanced boot options screen. And from here, you have options to Repair Your Computer.

You have Safe Mode options, and many other options when Windows starts up with Windows 7. I’m going to choose Repair Your Computer, and it’s going to start the Windows operating system into a recovery mode that allows me to choose a number of different startup options. The first prompt you’ll get for the system recovery options, is to select a keyboard.

In my case, it’s the US keyboard. It asks for my login prompt for this particular system. I’m going to choose my login information and password. And now we have the recovery tools available. Startup repair is right at the top. Some of the other options we’ve talked about during this video have needed the command prompt, and that’s how you would start those in Windows 7 as well.

If you’re running Windows 8, the user interface looks a little bit different, but the options are very similar. When you press F8, you’ll get different options to Continue, Turn Off Your PC, Use Another Operating System, or choose the option to Troubleshoot. When you press Troubleshoot, you have the option to Refresh Your PC, Reset Your PC, and then you have Advanced Options. Under the Advanced options you have System Restore, Command Prompt, System Image Recovery, Startup Settings, and then to get Startup Repair to run, we’d simply choose Startup Repair.

If you’re running Linux, then you’re probably using a boot loader called GRUB, or LILO. GRUB is the GNU GRand Unified Bootloader, and it’s very common to find on Linux systems. On older Linux distributions, you may find LILO, which stands for a Linux Loader. If either GRUB, or LILO, have been missing, or damaged, then your operating system isn’t going to load. These missing boot loaders can very often be overwritten by other operating systems.

So, if you have a Linux on one partition, and then you install Windows in the other partition, it may overwrite the GRUB, or the LILO boot manager that you were previously using. Fortunately, there are a number of live CDs for Linux that can repair these problems. You can re-install GRUB and hide the boot menu, or repair the file systems and much more during the startup process.

A number of device drivers and services will start on your computer. Sometimes, this doesn’t always go as planned. If you have a device that’s not working properly, you might want to check the Device Manager, and see if any particular service is listed that might have an error message next to it. It might also be able to find information in the Event Viewer, as well.

Sometimes, there is a bad, or corrupted driver, and simply replacing, or updating, the driver can solve this problem. If you see a message that one, or more services, failed to start, it could certainly be because there is bad hardware. If you aren’t quite certain of the problem, you might want to try starting the service manually.

There are often sometimes account permissions associated with the service that you are starting that are not using the defaults, and of course if those aren’t correct the service won’t start properly. You might also want to check your service dependencies, to make sure that all of the other services that are needed are also starting, before you start the service.

If the problem is related to a Windows service, then you want to check the operating system files. If this is a service that you installed, or an application that is running the service, you may want to re-install the application so that all of those files are refreshed.

To manage Windows services, you do all of this through the Windows Services utility. You can find a service that you’d like to manage, right mouse click, and choose Properties. You’ll then see the properties for this particular service that will tell you more information about the service. It will tell you what happens when the system starts up, and whether this is something that starts automatically, or manually.

And then you have the option to start, stop, pause, or resume the service from here. You can also choose the dependencies tab, and see what other system components are required to have this particular service start successfully.

A dynamic link library is a bit of code that’s installed on your computer that multiple applications can use. They simply write information to this library, rather than programming everything from scratch themselves. And it’s not uncommon for many different applications to use a well-known library.

The library versions, though, are very specific. Application developers are writing their software to use a particular type of library, and a particular version of that library. That means you have to have exactly the right version of the DL installed on your system. Earlier versions of Windows would mismanage this process.

When you tried to install a newer version of the DL, it would delete the older version, which could break applications that relied on that previous version. Modern versions of Windows use features known as Windows file protection, and Windows Resource protection, so that you’re able to have multiple versions of a DL on your system. And you don’t have any conflicts between any of those versions.

The file types in your Windows operating system will be associated with a particular application. For example, any file that ends in docx is going to be a Microsoft Word document. Anything that’s an xls is a Microsoft Excel document. These associations can, of course, be changed.

So when you try to start a docx file, it starts a different program than Microsoft Word. But, you could have a problem where the wrong association is made for that file type, and you might see a problem such as a file failing to open a particular application. You can configure these file associations in Windows Vista, and Windows 7, Windows 8 and Windows 8.1 from the Control Panel under the default program’s applet.

Under this applet, you can get a list of all of the associations, so you can see all of the different extensions. You can view a description of those extensions, and then you can define what application runs whenever you click on one of these file types. If you’re running an older application that relies on an older operating system, you might still be able to run it in your new operating system by using the compatibility tab of the application.

If you look at the properties of the application, there will be a compatibility tab in those properties, and then you can choose exactly which operating system is most compatible with this application. If you’re finding your system is performing slowly, you might want to look at more details about where this problem might be occurring.

The first place you should go is the Task Manager. This provides you with real time views of memory utilization, network usage, and much more. You can look for high CPI utilization, and anything that might be using a lot of disc access, or network access. You can even break down the performance view, and get more of a graphical view over time, so you can easily see when the problems might be occurring.

Slow systems might also be caused by problems with the operating system. So, running Windows Update, and having the latest version of patches on your system, is always a good idea. You might also want to check your drive space. When you run low on that drive space, it creates a problem for files to store temporary information and can cause everything to run slowly on your computer.

If you have a laptop, you may want to check to see if it’s running a power saving mode. In those modes, your CPU automatically runs slower, so that it uses less battery. And of course, this could be caused by malicious software. So you might want to run an anti-virus and anti-malware scan, and make sure there’s nothing unusual running with your operating system.

A kernel panic is something you might see in Unix, in Linux, or in Mac OS. And this is very similar to a Windows blue screen of death. This is an unrecoverable error that happens to the operating system, and when this occurs the entire system halts completely.

In any of these operating systems, you may be able to see the error message when it occurs to find out what might be causing the problem. In Mac OS, you may not have anything on the screen. You may need to restart and look at the logs to see where this problem occurred.

And it might provide you with some direction you can go for troubleshooting, to help understand the problem you’re seeing is related to bad hardware, or if there might be a problem with the operating system. And one rather annoying, but easily fixable, operating system problem occurs when you have multiple monitors on your system, and they’re not aligned properly.

Whenever you’re configuring multiple monitors, you’re able to adjust exactly where they are relative to each other. In this particular example, you can see monitor one and monitor two are next to each other, but you notice they are misaligned. They’re only connected in these two areas, so if you wanted to move my mouse from monitor one to monitor two, it has to be from the top of monitor one and it moves over onto the bottom of monitor two.

In most cases, you want to be able to line these up exactly, so that as you move the mouse from one to the other, it’s able to move to the exact same area of the other monitor. You can do this by simply clicking on the monitor display, and dragging it into the right alignment, so that your mouse is able to move properly from one to the other.