What is the problem?
Your laptop randomly loses its wireless network connection while the connection management utility reports no wireless networks found. This issue can also be seen in the Windows* System Event log in the form of numerous 500x events with the wireless driver as the source.
This issue impacts Intel® PROSet/Wireless Software 13.0.x and 13.1.x releases specific to the Intel® PRO/Wireless 3945ABG Network Connection.
What is causing the problem?
An adapter internal error related to power management has occurred. This problem only occurs when some level of adapter power savings mode is enabled.
How to Fix
Beginning with Intel® PROSet/Wireless Software version 126.96.36.199, this issue is resolved. Upgrade your software to resolve this issue.
Disable all adapter power savings modes by selecting the lowest power management setting, which enables the maximum wireless network performance.
Resolving Wi-Fi network connection issues