How to run MemTest86+ from a flash drive
Backup the USB flash drive you will be using before running the install program as it will be wiped (if you select format) during the create process.
Download: Auto-installer for USB Key (Win 9x/2k/xp/7)
Unzip the file into a folder on your desktop. Run Memtest86+ USB Installer.exe. You will see the following window:
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Click I Agree:
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Select your flash drive from the dropdown and check We will format x:\ as Fat32.
Click Create. When it completes you will see this window.
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Click Next:
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Click Finish. Your flash drive is now ready to use.
Leave the flash drive in then reboot. Select the Flash drive to boot from.