here is an article about this problem on the microsoft website, I copy and paste here. Click on the link of the source to read more details.
Good luck mate
CAUSE
Windows XP SP3 introduces a new .dll file that is named Wlanapi.dll. This file is installed in the %WINDIR%\System32 folder. Certain device driver installations for some third-party wireless network adapters also install a Wlanapi.dll file in the %WINDIR%\System32 folder. If such a file is installed in this folder before you install Windows XP SP3, the Wlanapi.dll file that is associated with the network adapter is replaced by the file from the Windows XP SP3 installation.
RESOLUTION
To resolve this issue, check the Web site of the wireless network adapter's manufacturer for the latest device drivers that are available for a Windows XP SP3-based system. Then, download and install the latest device drivers for the wireless network adapter.
Source(s):
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