Troubleshooting Operating Systems – CompTIA A+ 220-802: 4.6

Our operating systems can have problems, and when issues arise the resolution isn’t always obvious. In this video, you’ll learn how to troubleshoot slow system performance, DLL management, compatibility errors, boot issues, and spontaneous shutdowns.

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If your operating system is running slow, you may want to make sure that you’ve got the latest version of everything. So try running Windows Update. Make sure you have the latest security patches and operating system patches. This might also allow you to update some additional drivers, all by using Windows Update.

Windows can also begin to run very slowly if it’s running out of disk space. So you may want to check and make sure that you have plenty of available disk space. And if you’re accessing a lot of files, you may want to run a defrag just to make sure that your inefficiencies aren’t caused by files that may be scattered on different places on the drive.

If you’re running a laptop, one of the configuration options you have is to always run the CPU at a slower speed if it doesn’t have power. That allows you to have a much longer battery time. But it also means that your system is going to run slower. So check your BIOS configuration for those slowdown down options and make sure that you’re not missing any CPU cycles just because you happen to be running away from AC power.

If you look at your Task Manager, you should be able to see all of your applications. And you can see exactly how many resources each app is using. So look through your list in Task Manager and look to see if any particular app is using a lot of CPU utilization. You also might want to look at some of the input/output statistics. Some of the slowdowns may be because you’re reading or writing to your hard drive.

And of course, sometimes slowdowns are caused by malicious software. So you may want to run a scan in your antivirus or your anti-malware application to see if someone might have slipped something really bad onto your machine, that’s slowing everything down for you.

If your operating system isn’t even starting, then we’ve got other places that we should look for problems. One is the Device Manager and the Event Viewer to see if anything might not be loading properly during start up. Or maybe you can find an error message or more details about a problem that’s all saved in your Event Viewer. Sometimes just a bad driver can cause a problem for your entire Windows desktop. So finding that one specific problem will get you halfway to solving the overall issue.

Sometimes when you’re starting your system, you’ll see a message pop up that says one or more services failed to start. Sometimes you know exactly what it might be referring to. But more often than not, we’re not really sure what problem we’re having with the Windows service. So we want to gather more information.

You might want to go to your Windows services and begin starting services manually to see if you can get any of them to fail. Then at least you know which ones are causing a problem for you. Make sure that your account permissions are set properly in the service so that they are starting properly with a service account or with an account that has the rights to do what it needs to do.

Look at any dependencies for that service. Maybe it’s not starting because another service has to start first. So as long as you start them in order, they’ll work properly. But make sure there’s no dependencies that you’re waiting on.

If it’s a Windows service, then you want to check the system files that actually run that service. And it may require that you install the application again that manages that service, so that it rebuilds and reconfigures everything for that service to start properly.

Microsoft Windows has a capability called a dynamic link library. This is some software that’s in your Windows operating system that can be used by many applications, even third-party applications. These applications, instead of writing this code that would be commonly used and redundant across all the applications, they can all simply write to this central dynamic link library to perform the functions that they need. It makes it much more efficient to do development work. It also makes things more efficient for the operating system.

The challenge you have is that these DLLs have different versions. They might all have the same name, but there might be minor differences between them. And applications are usually written to use a very specific version of a DLL. In older versions of Windows, you have a lot of problems trying to manage these version numbers. You’d overwrite the DLL with a newer version and some of your older applications would not work properly with it.

And so in the latest version of Windows, there’s a couple of different technologies, one called Windows File Protection and Windows Resource Protection. And they’re in place to make sure that your system DLLs and your third-party DLLs are not going to have any conflicts. You can have all of those dynamic link libraries on your system simultaneously and your application will use the correct DLL for that app to work properly.

You’ve probably seen in your data files that you’re storing, that they all have some very unique extensions. You might save a Word document and it has a .docx extension. You might save a PowerPoint presentation and it has a .pptx extension. It’s this extension that tells Windows what application should run, to be able to use that particular data file.

This list of applications is all inside of Windows. And they can also be modified. Sometimes they can be modified by third-party applications. So one day you’re using PowerPoint to do your presentations, you load some new software, and now suddenly the PowerPoint presentations don’t start automatically when you click on that particular .pptx file.

So you might want to go into your Windows file associations. In Windows XP, in your folder options, you can look at the File Types tab. And in Windows Vista and Windows 7, you go into your Control Panel and look at the Default Programs applet.

If you’ve upgraded your operating system and you notice that some of your old applications aren’t working properly, you might want to try changing the compatibility for those applications. This is a nice capability built into Windows that allows it this backwards compatibility. If you want to look at the application properties that will bring up this dialogue box, and under the compatibility tab, you can decide to run this program in compatibility mode for, and you can choose the operating system that would apply for this particular application. Sometimes those older apps that haven’t been updated to a new version of Windows can still run just by using this compatibility mode.

If your computer isn’t starting at all, there’s a number of troubleshooting steps we can pass through. If you’re getting a message that there is an invalid boot disk, you might want to see if there’s any USB devices plugged in. Your BIOS might be configured to try to boot from those devices, instead of building from the local hard drive. You can also go into the BIOS configuration itself and modify what devices should start first for your computer.

You might also see a message that pops up, that says operating system not found. That’s usually when you’re accessing a drive that’s a boot device, but there’s no boot loader anywhere on that computer. You might have to go into the Recovery Console or the Windows Recovery Environment and run a chkdsk to see if your operating system is indeed on that computer system. Or maybe the drive is simply pointing to the wrong place for the operating system. Maybe you just need to update the Master Boot Record and then your system would be able to find the operating system properly.

On older versions of Windows, like Windows XP, you might see a message that says your NTLDR is missing, N-T-L-D-R. These are very important system boot files. And if for some reason they are deleted from your computer, then obviously nothing is going to start. You would commonly start your computer with a boot disk that allows you to copy those files back to the hard drive, restart your system, and your Windows should be up and running.

An important system file that gets things running on your computer on Windows XP is the boot.ini file. On newer versions of Windows, Windows Vista and Windows 7, you have the bootcfg, Boot Configuration Database. If you are having problems with your boot.ini, you can manually edit that in a text editor.

But Windows Vista and Windows 7 have this special database format. It’s no longer a text file. So if you need to rebuild that, you would choose from the Recovery Console, bootcfg /rebuild and it will rebuild that boot configuration database so that then you can choose the operating system that needs to load when you start your computer.

If your computer did not shut down properly and you’ve restarted your computer, you may notice that it does not go directly into Windows. It may run a Windows Error Recovery window that then runs an autochk of the drive and the file system. That way it make sure that everything is still exactly where it should be, so that it knows it can start Windows without running into any problems.

And if Windows does start up and we see nothing, we see a black screen, there’s no user interface, there’s no login screen, then we probably have a problem with the device driver that’s running the video for our system. We may want to update that video driver by starting in Safe Mode. You might also want to start in the graphics mode for VGA graphics or lower resolution graphics with Windows, so that you can at least get the screen to a point where you can load up the new drivers.

You might also be able to recover from a previous version of Windows or from your backups. There’s also a Repair Mode in Windows Vista and Windows 7 that might help. And these might get you past some of these video glitches so that you can get back to the Windows desktop.

A message that every Windows user hates to see is that blue screen of death, that Windows stop error. And that usually pointing towards bad hardware or a device driver that’s somehow gone bad. You may be able to use the last known good configuration, the System Restore functionality, or simply roll back a driver to a previous version, if you just updated one and started seeing this mode.

One way to get around this problem is to perhaps use the last known good configuration. You can also go back to a previous point in time, using the System Restore functionality. And if you’ve just installed a new driver and now you’re starting to see this blue screen of death, you might want to use the Windows Rollback Driver functionality to go back to the previous version. You may have to start in Safe Mode so that you can get through these driver problems to be able to run things like the Rollback Driver functionality.

If this is a piece of hardware that is seated inside of your computer and you think that’s what’s causing the problem, you might want to pull it out and reseat it to make sure it’s got a very good connection. Obviously, not all hardware is going to apply here. But if this is something new that you’ve added into the inside of your computer, it’s worth making sure that it’s got a good connection on the motherboard.

And lastly, if you’re just not sure where the problem is coming from, you might want to run a hardware diagnostics. Make sure that your hard drive is working normally, that the memory is performing as it should, so that these blue screen messages can be cleared up once and for all.