ok, then do the following please to remove any corruption in Windows that can be causing this.
First, restart the computer and keep tapping F8 until you get to a menu.
Choose Safe Mode
Once windows has loaded, uninstall the adapter.
than do the following please
Download CC Cleaner (free) from hereCC Cleaner
(Click Download Latest Version on the top right)
Run it and let it scan and repair your registry.
Once done, restart the computer
Click Start, All Programs, Accessories, right click on Command Prompt and select Run As Administrator.
A black window will open.
Type in it
press enter and when it has completed, type in
It will give a message "the type of the file system is NTFS cannot lock current drive.
chkdsk cannot run because the volume is in use by another process. Would you like to schedule this volume to be checked the next time the system restarts y/n" Say Y, press enter and restart the computer.
Than install the adapter and tell me if it is now working please Simon.