After 25 years of successful PC troubleshooting, I was almost defeated last week. Almost. I finally fixed the problem. Hooray! But there goes 100 hours of my life that I won’t get back. However, I learned a few more things about PC troubleshooting along the way, and will share them with you here.
Since the early 90’s, I have been one of those “go to” guys that friends and family called when they had a PC problem. Being good at PC troubleshooting is a combination of theory and practice. It’s important to understand the theory of how things work, but practice is paramount. Ideally, you have diagnosed and fixed something before. Your experience provides the pattern of the problem and the probable solution.
PC troubleshooting hardware problems is usually straightforward. Typically it is a hard drive or memory problem – and there are tools to diagnose these. Heat-related intermittent circuit board failures have the typical symptom of a laptop fan running in high gear for no apparent reason. And with modern PC so highly integrated it is usually cheaper to replace the computer.
In the old days, you could usually identify a bad board and replace it easily. Not so today. But hardware failures rare; PC’s are pretty reliable. And when they fail, there is often nothing you can or want to do anyway.
My general advice is to plan ahead for a dead PC. Assume your laptop could die at any time. Focus on document backups. This is very easy. I use SyncBack Free and a network drive. Once programmed, SyncBack will automatically backup copies of your documents every day. It also doesn’t hurt to synchronize your documents onto a cloud service like Dropbox, so you have an off-site backup, as well.
But when it comes to the operating system, PC troubleshooting is a whole different story. Installing software – either on purpose or through viruses – can break your operating system. Even Windows updates can cause failures. Even “tools” that you install to clean and maintain your PC, or antivirus programs, can cause failures.
The worst OS failures are caused by bad drivers and Windows Registry corruption. Drivers are little pieces of software that enable Windows to communicate with hardware and devices. Drivers are typically installed by Windows Update whenever you plug in a new USB device, for example. Often, applications install drivers, as well. The Windows Registry is like a notebook that Windows continuously uses to keep track of all the things it needs to know. It is a database. A lot of the information in the Registry may be quite old as Windows and application programs are good at adding stuff but not at removing it. Sometimes, the Registry becomes corrupted with bad or incomplete information.
All in all, device drivers and Registry entries are too complex for most humans to understand. Your computer probably has more than 250 drivers and more than 100,000 Registry entries. Good luck with that!
PC Troubleshooting Plug and Play Devices is hard
Last week my trusty old Toshiba laptop developed a problem. Normally, I use a single monitor, mouse and keyboard to interface with two laptops (one for work, and another for radio stuff.) I move between these with a KVM switch. Both PC’s run Windows 7 64-bit. The Toshiba refused to recognize the mouse or the keyboard, or recognize the USB hub in the KVM. It also failed to startup its internal USB camera. Here is the initial PC troubleshooting process I followed:
- Remove the laptop from the KVM switch and plug the keyboard and mouse directly. No go. But at least eliminated the KVM USB hub as the source of the problem.
- Checked Device Manager. Windows was recognizing the keyboard and mouse correctly, but refusing to install drivers.
- Checked for hard drive errors using Windows Check Disk. None.
- Checked for corrupt system files using Windows System File Checker. Found something. But while the tool told me there was a problem, it also told me that it could not tell me what it was. Don’t you love Windows?
- I tried several System Restore configurations. They failed but did not tell me why.
- From Tosiba’s web sites, I updated my BIOS and core laptop drivers. No change.
- Opened Windows Event Viewer and looked for any system error reports after a boot-up. The theory is that if a system file is failing there should be an error posted. None. Boy, this must be a very deep and subtle problem.
In football, when you are stuck deep in your own zone with nowhere to go, you punt. So, at this point in my PC troubleshooting I would try a punt. Perhaps this was a good time to upgrade to Windows 10. After all, the upgrade should install all of the correct files, right?
- Ran Windows 10 upgrade. After an hour, it simply stalled at 32% while installing drivers at 6%. Hours went by. Nothing progressed. Did a cold restart by holding down the power button. The laptop then re-booted and rolled back to Windows 7 in its previous broken state. Web searches indicated this as a well documented problem with no clear solution. But most people seemed to agree that it somehow related to bad USB problems, and recommended unplugging all USB devices, turning off the network card, and installing from a disc.
- Created a Windows 10 upgrade disk. I did what they call a Clean Boot and also turned off all the non-Windows devices and services. No change. Still stalled.
- At this point, I reviewed the Windows installer error log and found mention of some failures for certain driver entries in the Registry. I ran Device Remover and tried to remove all the USB drivers that that appeared to have problems. Ran the Windows 10 upgrade disk. No change. Still stalled.
Fortunately, the Windows 10 upgrade does a great job of rolling back to Windows 7 when it fails.
At this point, four days into my PC troubleshooting, there was nothing left to do but reinstall Windows 7. Although I had documents all backed up, I wanted to avoid all the work of reinstalling programs with a new Windows 7 installation. Fortunately, if you have a genuine Windows 7 installation, you can do what is called a non-destructive install. You basically run your installation disk and select Upgrade – see the instructions here. This is not exactly a secret, but something Microsoft does not publicize for some reason.
- Sigh. The Windows 7 reinstall gets stuck at 49%. Just plain stops and sits there forever. This seemed to be the same problem as with Windows 10. Now I am more convinced then ever that there is a driver or Registry corruption that is baffling not only me, but also the Windows Installer. In installer log contained numerous references to “bailing out”.
- Fortunately, researching this Windows 7 installation problem gave me some new information. I found reference to a Microsoft tool called the System Update Readiness Tool. The description of this tool says “Windows corruption errors may prevent Windows updates and service packs from installing. For example, an update might not install if a system file is damaged. The System Update Readiness tool may help you to fix some Windows corruption errors.” This sounded like my problem alright. Maybe this time?
- So, I ran the System Update Readiness Tool and the did another Windows 7 non-destructive install. It worked. Everything is back to normal.
The good news is that five days of PC troubleshooting ended in success. I still don’t know exactly what the problem was, other than some sort of corruption of drivers and/or Registry settings relating to plug and play USB devices. Plug and play is a wonderful thing, until it isn’t. Good luck!