It happens because when your computer sleeps the power to USB devices will be disconnected, and after resuming, Windows will not perform the check operation of new connected devices.
After reconnecting it will scan for new devices and it will work fine.
Instead of unplugging and plugging the adapter every time, just go to Device Manager and right click on any device and perform scan for new hardware changes. It will detect your USB device and do initialization of Device.
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When a Windows 7 or Windows Vista-based PC resumes from sleep or hibernation, the following USB device problems may occur:
-You may receive an error message.
-The USB device may not work.
-The USB device may not work as expected.
How to troubleshoot the problem
To troubleshoot this problem, try one or more of the following methods:
The "USB selective suspends settings" option in the Power Options may be Enabled.
Click Start, type Power Optionsin the Search box and then click Power Options from the returned list
-Click Change plan settings for the selected Power plan
-Click Change advanced power settings
Expand USB settings and then USB selective suspend setting and change the setting to Disabled for the option for On battery: or Plugged in:
-Click OK on the Power Settings window and click Save changes on the Edit Plan Settings window
Important: This is a default power setting , disabeling this setting will cause additional battery power consumption when your mobile PC is in Sleep or Hibernation mode and unplugged.
The "Allow the computer to turn off this device to save power" setting in Device Manager may beEnabled.
-Click Start, type Device manager in the Search box and then click Device Manager from the returned list
Click to expand USB Root Hub and click the Power Management tab
Uncheck the option to Allow the computer to turn off this device to save power and click OK
Note: You may see multiple listings for USB Root Hub, uncheck this option for all USB Root Hubs.
Close the Device Manager :
Important: This is a default power saving setting, disabeling this setting will cause additional battery power consumption when your mobile PC is in Sleep or Hibernation mode and unplugged.
Unplug the USB device, wait about five seconds, and then plug the device back in. If you are using a hub, unplug the hub, wait about five seconds, and then plug the hub back in.
-If you are using a USB hub, try to use the device without the hub. If you verify that the hub is the issue, use one of the following methods, depending on your scenario:
-If the external power supply for the hub is not connected correctly, connect the external power supply correctly.
-If there are too many devices plugged into the hub, unplug some devices.
-If the hub does not function correctly, you may have to replace the hub.
-If your USB device is connected to a USB port on a portable computer docking station, try to connect the device directly to the USB port on the portable computer. If you verify that the problem is caused by the docking station, and the steps in this article do not resolve the problem, contact the manufacturer of the docking station for additional assistance. For information about how to contact the manufacturer of the docking station, visit the following
Microsoft Web site:
Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.
-If the USB device is powered from an external source, make sure that the power from the external source is available to the device when the computer resumes.
When you use USB 1.0 devices on a USB 2.0 capable system, the device may not function correctly or may have performance issues. To resolve these issues, you may have to replace the USB device with a USB 2.0 capable device.
Install the latest updates for Windows and install the latest drivers for the USB device.
-To install the latest updates and drivers, visit the Microsoft Windows Update Web site.
http://update.microsoft.com If there are no updates available for the USB device on Windows Update, you may have to contact the hardware manufacturer for information about updates.
For information about how to contact a vendor, visit the following Microsoft Web site: