Wireless scan shows stale SSIDs

Question

Windows 7, SP 1, 64-bit. Described issue seen with both internal Centrino Advanced-N 6235, and external USB wifi, so I'm calling this an OS issue, not a driver issue.
If I am connected to an access point, and that access point is turned off, both the Wireless Network Connection pullup and
netsh wlan show networks (run as administrator) continue to show that I am connected to the access point.  This persists for 20-30 seconds or more, including multiple refreshes of the scan. If I was
not connected to that access point, it continues to show in the scan as if it were available for connection.
Basically, the scan list contains stale SSID information, and I would like to find a way to flush the stale SSIDs from the list so that it shows only current SSIDs.
Prior to SP 1 there was a hotfix for what looks like the identical problem, observed in a slightly different way:
    "This issue occurs because the
WLAN API provides an old BSSID to the application after you move the computer to a new access point."
https://support.microsoft.com/en-us/kb/2385405
In that case the user was connected to an access point prior to hibernation, moved the laptop to a location out of range of that access point, came out of hibernation, and the WLAN API continued to report connection to the out-of-range access point.

Answer 1

Hi linuxilike,
As you stated it has something to do with the WlanScan function and WlanGetAvailableNetworkList function.
Here are links for reference of the WlanScan function and WlanGetAvailableNetworkList function :
WlanScan function
https://msdn.microsoft.com/en-us/library/windows/desktop/ms706783(v=vs.85).aspx
WlanGetAvailableNetworkList function
https://msdn.microsoft.com/en-us/library/windows/desktop/ms706749(v=vs.85).aspx
As the descriptions stated :
 "When the WlanScan function is called, the native 802.11 Wireless LAN driver may flush the current list of available wireless networks before the scan is initiated. "
"The WlanGetAvailableNetworkList function allocates memory for the list of available networks returned in the buffer pointed to by the ppAvailableNetworkList parameter when the function succeeds. The memory used for the buffer pointed to by ppAvailableNetworkList
parameter should be released by calling the WlanFreeMemory function after the buffer is no longer needed. "
The Wlanscan function is related to the Wireless LAN driver,it seems that Wireless LAN driver didn`t flush the current list of available wireless networks before the scan is initiated ,or the WlanFreeMemory function didn`t work .
Have you tried to update or reinstall the Wireless LAN driver to have a check ?
" Is there, for example, a timeout that can be set to 0 so that SSIDs expire from the list the first time they are absent from a network scan?"
Do you mean the expired SSID will disappear after several refresh scan or the issue will persist?
Best regards
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