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Please uninstall Avast! antivirus during troubleshooting. It's known to contribute in BSOD-s avast! Uninstall Utility | Download aswClear for avast! Removal
. Use Microsoft Security Essentials - Microsoft Windows
Run these tools and delete anything they may find:
ESET online scanner:
Error code F4 is usually a storage/hard driver related crash.
Upload a screenshot of your hard disk using crystal disk info:
Run Disk Check on your hard disk for file system errors and bad sectors on it:
Hard drive test both short and long with:
Test the hard drive with the DOS version of seatools at last.
You may also go through these:
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:
Let us know the results.