Installing the Microsoft class driver(s) for USB Audio devices. So external USB peripherals will not work with it; this includes USB Audio devices as well as things like “on the go” USB hard drives etc. Is the recording function ready in the native USB audio 2.0 driver? Are there any device you use for verifying the recording function.
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Last updated
April, 2015
OS version
Windows 10
Windows 8.1
Applies to
Device manufacturers of CDC Control devices
Microsoft-provided in-box driver (Usbser.sys) for your Communications and CDC Control device.
In Windows 10, the driver has been rewritten by using the Kernel-Mode Driver Framework that improves the overall stability of the driver.
Improved PnP and power management by the driver (such as, handling surprise removal).
Added power management features such as USB Selective Suspend.
In addition, UWP applications can now use the APIs provided by the new Windows.Devices.SerialCommunication namespace that allow apps to talk to these devices.
Usbser.sys installation
Load the Microsoft-provided in-box driver (Usbser.sys) for your Communications and CDC Control device.
Note If you trying to install a USB device class driver included in Windows, you do not need to download the driver. They are installed automatically. If they are not installed automatically, contact the device manufacturer. For the list of USB device class driver included in Windows, see USB device class drivers included in Windows.
Windows 10
In Windows 10, a new INF, Usbser.inf, has been added to %Systemroot%Inf that loads Usbser.sys as the function device object (FDO) in the device stack. If your device belongs to the Communications and CDC Control device class, Usbser.sys is loaded automatically.You do not need to write your own INF to reference the driver. The driver is loaded based on a compatible ID match similar to other USB device class drivers included in Windows.
USBClass_02
USBClass_02&SubClass_02
If you want to load Usbser.sys automatically, set the class code to 02 and subclass code to 02 in the Device Descriptor. For more information, see USB communications device class (or USB CDC) Specification found on the USB DWG website. With this approach, you are not required to distribute INF files for your device because the system uses Usbser.inf.
If your device specifies class code 02 but a subclass code value other than 02, Usbser.sys does not load automatically. Pnp Manager tries to find a driver. If a suitable driver is not found, the device might not have a driver loaded. In this case, you might have to load your own driver or write an INF that references another in-box driver.
If your device specifies class and subclass codes to 02, and you want to load another driver instead of Usbser.sys, you have to write an INF that specifies the hardware ID of the device and the driver to install. For examples, look through the INF files included with sample drivers and find devices similar to your device. For information about INF sections, see Overview of INF Files.
Note Microsoft encourages you to use in-box drivers whenever possible. On mobile editions of Windows, such as Windows 10 Mobile, only drivers that are part of the operating system are loaded. Unlike desktop editions, it is not possible to load a driver through an external driver package. With the new in-box INF, Usbser.sys is automatically loaded if a USB-to-serial device is detected on the mobile device.
Windows 8.1 and earlier versions
In Windows 8.1 and earlier versions of the operating system, Usbser.sys is not automatically loaded when a USB-to-serial device is attached to a computer. To load the driver, you need to write an INF that references the modem INF (mdmcpq.inf) by using the Include directive. The directive is required for instantiating the service, copying inbox binaries, and registering a device interface GUID that applications require to find the device and talk to it. That INF specifies 'Usbser' as a lower filter driver in a device stack.
The INF also needs to specify the device setup class as Modem to use mdmcpq.inf. Under the [Version] section of the INF, specify the Modem and the device class GUID. for details, see System-Supplied Device Setup Classes.
For more information, see this KB article.
Configure selective suspend for Usbser.sys
Starting in Windows 10, Usbser.sys supports USB Selective Suspend. It allows the attached USB-to-serial device to enter a low power state when not in use, while the system remains in the S0 state. When communication with the device resumes, the device can leave the Suspend state and resume Working state. The feature is disabled by default and can be enabled and configured by setting the IdleUsbSelectiveSuspendPolicy entry under this registry key:
To configure power management features of Usbser.sys, you can set IdleUsbSelectiveSuspendPolicy to:
'0x00000001'
Enters selective suspend when idle, that is, when there are no active data transfers to or from the device.
'0x00000000'
Enters selective suspend only when there are no open handles to the device.
That entry can be added in one of two ways:
Write an INF that references the install INF and add the registry entry in the HW.AddReg section.
Describe the registry entry in an extended properties OS feature descriptor. Add a custom property section that sets the bPropertyName field to a Unicode string, 'IdleUsbSelectiveSuspendPolicy' and wPropertyNameLength to 62 bytes. Set the bPropertyData field to '0x00000001' or '0x00000000'. The property values are stored as little-endian 32-bit integers.
For more information, see Microsoft OS Descriptors.
Develop Windows applications for a USB CDC device
If you install Usbser.sys for the USB CDC device, here are the application programming model options:
Starting in Windows 10, a Windows app can send requests to Usbser.sys by using the Windows.Devices.SerialCommunication namespace. It defines Windows Runtime classes that can use to communicate with a USB CDC device through a serial port or some abstraction of a serial port. The classes provide functionality to discover such serial device, read and write data, and control serial-specific properties for flow control, such as setting baud rate, signal states.
In Windows 8.1 and earlier versions, you can write a Windows desktop application that opens a virtual COM port and communicates with the device. For more information, see:
Win32 programming model:
.NET framework programming model:
Related topics
External Hard Drive Is Not Showing Up/Not Appearing When Connected. How To Fix It?
An external hard drive is similar to the type of hard drive (HDD) that you can find inside your computer. An external hard drive is, of course, connected outside of the computer, thus making it portable, and easily transported, stored, and connected to other systems. Some external drives use the data cable for power sourced from the computer, whilst others require a separate power adapter.
The advantages of external drives are that they are portable, can provide mass additional storage, and are easy to use. These drives are very useful when you need to use different computers and have access to your data whenever you need it. External hard drives are capable of storing terabytes of data and are often used to backup files (in case the internal hard drive becomes damaged, corrupted, and so on). External hard drives provide excellent additional storage, especially if you use a laptop computer, since it is more difficult to replace a hard drive in a laptop (for one with larger storage capacity) than a desktop.
You may already have an external hard drive but experience problems accessing it in the Windows operating system. Connecting an external hard drive should be simple, but it might not appear when connected to the computer (the drive is not detected). This is a common problem that can be straightforward to resolve. Follow the guide below to make your external hard drive/s visible in Windows.
Table of Contents:
It is recommended to run a free scan with Combo Cleaner - a tool to detect malware and fix computer errors. You will need to purchase the full version to remove infections and eliminate computer errors.
Run Windows Troubleshooters
Firstly, run the Windows Hardware and USB troubleshooter. Windows includes a number of troubleshooters designed to quickly diagnose and automatically resolve various computer problems. Troubleshooters cannot fix all problems, but they are a good place to start if you encounter a problem with your computer, operating system or connected devices. To start troubleshooting, go to Settings and type 'troubleshoot', select 'Troubleshoot' from the list.
Find the 'Hardware and Devices' troubleshooter under 'Find and fix other problems', select it and click the 'Run the troubleshooter' button. It will start looking for problems relating to hardware and devices. Hopefully running this troubleshooter will help you to solve this problem and your external hard drive will appear.
Additionally, we recommend that you run the USB troubleshooter, which fixes problems with USB audio, storage, and print devices (such as thumb drives, USB hard drives, and USB printers). To run this troubleshooter, you must first download it from Microsoft official site. Download the troubleshooter and run it - see if it finds and fixes any problems relating to external hard drives that are not appearing.
Update Or Reinstall Device Driver
A device driver is software that informs the operating system and other software about how to interact with particular hardware. It is rather like a translator between software and hardware, since they often are created by different manufacturers, companies, or people. The driver facilitates smooth communication between hardware and software. In most cases, computers are unable to send and receive data correctly without drivers. If the appropriate driver is not installed, the device might not function properly. To reinstall an external disk driver you will need to use Device Manager. To open Device Manager, right-click the Start button and select 'Device Manager' result from the contextual menu or type 'device manager' in Search and click the 'Device Manager' result.
In Device Manager, you will see a list of devices connected to your computer. Find your external hard drive device (it should be under 'Disk drives' or 'Universal Serial Bus controllers') and right-click it. Then select 'Update driver' from the contextual menu.
You will be asked if you want to search for updated driver software automatically or to browse your computer for driver software. If you select the first option, Windows will search your computer and the Internet for the latest driver software for your device. If you select the second option, you must locate and install the drivers manually. Using this option requires having previously downloaded drivers on your computer or USB flash drive. We recommend that you select the first option and follow the instructions. If first option does not solve the problem, download the latest drivers from your external hard drive manufacturer's website.
You can also use third-party software to update your drivers automatically. We recommend Snappy Driver Installer (SDI), a powerful free driver updater tool for Windows that can store its entire collection of drivers offline. Having offline drivers gives Snappy Driver Installer the ability to have access to fast driver updates, even if there is no active Internet connection on your computer. Snappy Driver works with both 32-bit and 64-bit versions of Windows 10, Windows 8, Windows 7, Windows Vista, and also works with Windows XP. Drivers are downloaded through Snappy Driver Installer in 'driverpacks', which are simply collections (packs) of drivers for various hardware such as sound devices, video cards, network adapters, etc. It can also show duplicate drivers and invalid drivers. It separates the updates that require you to restart your computer so that they are easier to distinguish. You can download Snappy Driver Installer from here.
If updating drivers did not solve the problem, you might want to try to reinstall them. To do this, right-click your external hard drive device in Device Manager and select 'Uninstall device' option from the contextual menu.
You will be asked to confirm the uninstallation. Click 'OK'. Mark the 'Delete the driver software for this device' checkbox if you see this option. Restart the computer and Windows will reinstall the missing drivers automatically. If Windows does not install the missing (uninstalled) drivers, go to Device Manager and right-click your computer name and select 'Scan for hardware changes'. This should detect any missing drivers and install them.
Try A Different USB Port
It is possible that the USB port you are using to connect your external hard drive is not functioning properly, and why Windows does not show the drive when connected. Changing USB port might solve the problem, especially if there are different USB ports on your computer, such as USB 2.0 and 3.0. Some users have reported that connecting their external drive to USB 2.0 rather than USB 3.0 solved the problem and the external drive appeared. If you are using a USB Hub to connect external hard drive, try to use a USB port directly on your computer.
Disable USB Selective Suspend Setting
The Power Plan feature in Windows 10 is not new, since it was also available in earlier versions of the operating system. Power Plan is a collection of hardware and system settings that manage how your computer uses power. In this case, we are going to change the advanced power settings and disable the USB selective suspend setting. Type 'edit power plan' in Search and click the 'Edit power plan' result.
In the Edit Plan Settings window, you will be able to edit the settings of the power plan you are currently using. If you want to edit another plan, you can use the next window. Find and click 'Change advanced power settings'.
In the Power Options window, find the 'USB settings', expand it by clicking the '+' or simply double clicking USB settings. Do the same to 'USB selective suspend setting' and you will see whether this setting is enabled on both plugged (mains) and battery, or if it is disabled. If it is enabled, change battery and plugged to 'Disabled'. Click 'Apply' to save the changes, connect your external hard drive, and see if it appears.
Use Disk Management Tool
The Disk Management tool allows users to manage internal and external hard drives, flash drives, and optical disk drives. This tool can be used to format, partition drives, to assign drive letters and more. Disk Management is available in most Windows versions including Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, and Windows 2000. If you are experiencing problems while trying to connect your external drive, the Disk Management tool might help you to solve the problem. To open Disk Management tool, first launch the Run dialog box by right-clicking Start and selecting the Run option from the contextual menu, or simply press Windows key + R.
Once the Run dialog box is open, type the 'diskmgmt.msc' command and press Enter or click 'OK'.
If there a drive does not appear in File Explorer when you connect it to your computer, and Disk Management tool shows its status as 'Not Initialized', it is possible that the drive does not have a valid disk signature and was never formatted and initialized. If this is the case, right-click the drive and select the 'Initialize Disk' option. Note: this option will erase all data stored on your external hard drive.
If your external hard drive status is 'Offline', simply right-click it and select the 'Online' option. You can also try to unplug the external hard drive and plug it back in again. Then click 'Action' and select the 'Rescan Disks' option.
You can also shut down your computer and turn off your external hard disk (if you are using the one with a power cord), and then turn your computer on again and reconnect the external hard drive.
Try to connect the external hard drive to another computer. If it does not appear on the other computer, you know that something is wrong with the external hard drive and not the computer or operating system.
We hope this guide was useful and you were able to solve the problem with your external hard drive. If you know of other solutions to this problem, not mentioned in our guide, please share them with us by leaving a comment in the section below.
Video Showing How To Fix External Hard Drive If It Is Not Showing Up: