Driver Verifier

Transcription

Welcome back to your free windows 7 training. In the previous video I looked at the device manager. In this video I will look at the tools provided by Microsoft to trouble shoot device drivers. First I will look at the plug and play utility. This utility allows you to add device drivers to your system. Next I will look at the file signature verification tool. This tool confirms that files are from the correct sources and have not been tempered with or changed. Following this I will look at the direct x diagnostics tool. Aimed at direct x related hardware, but still a good tool for troubleshooting your hardware. Next I will look at the driver verification tool. This tool gives you a lot information that is useful for a programmer to trouble shoot drivers. Next I will look at the system information utility. This is a good utility for finding out general information about your system. Lastly I will look at the driver query tool. This tool allows you to export device driver data so that it can be read be read in software like excel. When you install new hardware in your windows 7 system, windows will attempt to automatically find a device driver for that device. It will first look in the staging area. This is located in the file repository directory located in the driver store found in your windows slash system 32 directory. If a driver is not found, windows can then check removable devices and windows update. Microsoft has supplied a command line tool called PNPUtil to make changes to the driver store. The tool has only has a few options. The first, minus a adds a device driver to the store. If you are creating an image and there is a high chance a particular hardware device will be added later, I would add it to the driver store before deployment. This saves the user being asked for the device drivers when the hardware is installed later. Notice that a wildcard can be used. This saves you having to type in the filename of the i n f file. Some i n f files have difficult names to type in. The next option, minus d, removes a driver from the driver store. When you add a driver to the driver store it will be called o e m and then a number. In this case, the last driver I added was given the number 9 so I will use the file name o e m 9 dot i n f. In some cases, you may want to install the device driver and also add it to the driver repository as well. You can do this by using the minus a and minus i switches. This combination of switches will add the driver to the repository as well as install the device driver in windows. Lastly if you want to know what drivers are in the repository, you can use the minus e switch. This will list all the drivers as well as the file names associated with that driver. For example, you can see that the last driver I added, the nvidiva driver, was given the name o e m 9 dot i n f. PNPUtil is a good tool for adding and removing device drivers. If you want to check the device drivers installed on your system, you can do this using the file signature verification tool. If I change to my windows 7 computer and in the start menu type in sig ver i f, I can launch the tool. All you need to is press start. The tool will check all the files on your local computer and make sure the signatures are correct. By doing this, you can check that the files have been supplied by a trusted source and have not been modified. Once complete, you will receive a message telling you if you files have been verified as being digitally signed. If you want more information, you can press the button advanced. By default, all the results will be saved to a log file. To view the log file, press the button view log. The log file will show you more information about the files that were checked, there versions and if the file is signed or not. The next tool I will look at is the direct x diagnostic tool. This can be run by typing in d x diag from the start menu. When you run the tool, the first question you will be asked is if you want to check that your drivers are digitally signed. Since it only takes one buggy driver to cause windows to become unstable, you can see why Microsoft encourages you at every opportunity to used signed drivers. On the system tab, you will get a lot of information about your system. This includes windows edition you are running, amount of memory and CPU information. Note down the bottom, you have the version of direct x that you are running. Useful to know when you have an application that requires a certain version of direct x. If you are running a 64 bit system, you have the option at the bottom to run the 64bit version of the direct x diagnostics tool. Regardless of whether you run the 64 bit or 32 bit tool, both tools give you the same information. On the display tab, you will be given information about the type of video card installed in the computer. This also includes information like the amount of graphics memory in the video card. There is also a section on direct x features. These include direct draw acceleration, direct 3 d acceleration and texture acceleration. These should be enabled by default, however if there is a problem, windows will switch to software rather than hardware acceleration. If you are having slow performance with you video, check this screen and make sure the features you required are available in the video card and have been enabled. If they are disabled and your video card supports them, you may need to update your video driver. The sound tab provides information about your sound card and the input tab provided information about input devices connected to your computer like keyboards, mice and joysticks. The next tool I will look at is the driver verification manager. Unlike the other tools, before this tool can be used it needs to configured. To run the tool, type verifier in the start menu. Once driver verifier manager is running, if I were to select the bottom option, display information about the currently verified drivers, I would not see any data since it has not been configured as yet. I will go back to the start of the wizard and select the top option create standard settings. On the next screen you need to decide which drivers you want to gather information from. In this case I will select the option all drivers, but I could capture data from only unsigned drivers, drivers from older versions of windows or specify the driver. Once I have select the option, I will be given a prompt telling me I need to reboot the computer for the changes to take effect. I will pause the video and reboot the computer. Now that the computer has rebooted, I can now run driver verifier manager again. To see the information that has been collected, I can select the option display information about the currently verified drivers. On the next screen, you can see the options that are being tracked and also the drivers. If you need to, you can change the options here. The next screen, you can see a list of counters. Most of this information won't mean much unless you have a programming background. However, if you have a lot of fault injected this may mean there is a problem with the driver. This information is generally useful for the developer of the driver. On the next screen, you can get counter information on a specific driver. These counters relate to memory use. If your driver has a memory leak, these counters will keep going up using all your free RAM. Over time, this will reduce the performance of your system. If you only want to get general information about a system, Microsoft has included the read only tool called system information. This tool will give you the same information device manager will give you plus additional information not available in device manger. To run system information, type system at in the start menu and select system information when it appears. Under system summary, you can find out general information about the system. For example, which edition of windows 7 it is running. You can also see information like the architecture of the system and which processor the system is running. Down the bottom of the screen you can see how much RAM is installed and also details about the virtual memory configuration including where the virtual memory file is stored. If I select hardware resources and then conflict sharing, like device manager this shows the resources that are being used on windows 7 and also if there are any conflicts on the system. With windows 7 and plug and play, resource conflicts are pretty much non existence, but if you do have a problem this will show you which devices are trying to use same resource. It is possible for devices to share resources, so if you get some entries in here it may not be a problem. You can also see information about the direct memory accessing or D M A on the system. The forced hardware is any hardware you have manually configured. Most devices you will find in modern systems you won't be able to change the settings anyway. After this you have "input output" , interrupts and memory. This information is available in device manager as well. In the components section this will give you information grouped by the component. For example, if I select C D rom I can see details about all the c d roms installed on the system. If I select network I can see information on all the adapters installed on the system as well as the protocols. If I a select multimedia, I can access information about the audio and video codec installed on the system. Information not available in device manger. System information also gives you access to the software environment. If I expand into software environment I can access a section on system drivers. Here you can see that the drivers are stored in the windows system 32 drivers directory. You can see what environment variables are configure on your system. You can see printer jobs, network connections, running tasks and the list goes on. This is a read only tool, but it is a great trouble shooting tool for working out what is installed and running on your system. The last tool I want to look at this driver query. This is a command line tool you can use to get information about device drivers installed on your system. If you run driver query without any switches you will get a list of all the devices on your computer. If you want to limit this list to only signed drivers use the slash s i switch. There is quite a lot of information listed already, but if you want more you can add the slash v switch for verbose mode. You can also change the format using the slash f o switch. This can be either table, list or csv format. In this case I have used list format. There is a lot of information here. If you want to import this information into software like excel, you could add the v switch for verbose mode and then the f o switch for csv. Excel can read csv files. If you then add the greater then sign you can direct the output to a file called drivers. The output will be saved in this case to a file called drivers dot csv. This file can then be read into excel. In most cases, to get a device to work in windows 7 it is just a matter of finding the correct driver. On the odd occasional you have problems the tools I have looked at in this video will help you trouble shoot the problem. Despite having these tools at your disposal, try the simplest option first of updating the device driver. Often a buggy device driver is fixed by updating it to the latest version. In the next video, I will look at configuring the power options for USB devices as well as configuring device drivers using group policy.