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Avast! antivirus often contributes in BSOD-s, please uninstall and replace with Microsoft security essentials. (To test)
Recommended antivirus program for Windows 7 based on stability compared to others:-
Do not start the free trial of Malware Bytes; remember to deselect that option when prompted.
Run a full scan with both (separately) once downloaded, installed and updated.
Please uninstall Spybot S&D, it;s sometimes known to corrupt and slow down the system.
Start Menu\Programs\Spybot - Search & Destroy Public:Start Menu\Programs\Spybot - Search & Destroy
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:
Free up the start-up, nothing except the antivirus is usually needed.
Run Disk Check on your hard disk for file system errors and bad sectors on it: Daemon Tools:
Please uninstall DAEMON Tools. It uses a driver
called sptd.sys which is known to cause BSODs in Windows 7. Uninstall the software using Add/Remove Programs. Reboot the system. Once the program is uninstalled, run sptd.sys uninstaller
to remove the driver from your system.
As an alternative, many people recommend the use of Total Mounter
or Magic ISO
Let us know the results.