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Update the Atheros network adapter driver from: ATHEROS drivers for Microsoft Windows (Atheros?????)
First remove anything related to it from Control panel. Click on the Start
► Control Panel ► Programs ► Uninstall a program ► Uninstall everything related to; Atheros. Delete remnants of its drivers/older drivers using Driver Fusion/Sweeper
4: kd> lmvm athrx
start end module name
fffff880`04222000 fffff880`043ad000 athrx T (no symbols)
Loaded symbol image file: athrx.sys
Image path: \SystemRoot\system32\DRIVERS\athrx.sys
Image name: athrx.sys
Timestamp: Thu Apr 22 00:13:20 2010 (4BCF4040)
Translations: 0000.04b0 0000.04e4 0409.04b0 0409.04e4
Replace Avast! with Microsoft Security Essentials (at least to test).
Free up the start-up, nothing except the antivirus is usually needed.
Run the System File Checker that scans the of all protected Windows 7
system files and replaces incorrect corrupted, changed/modified, or damaged versions with the correct versions if possible:
Run Disk Check on your hard disk for file system errors and bad sectors on it:
Let us know the results.