HP8440p-only boots Windows USB Flash - cannot boot other standalone programs

[Who-Knew]

Elitebook 8440p. Latest BIOS (F.60 - 2015) Win-10 (2004). 8GB RAM. Using MACRIUM Reflect for disk imaging. Ongoing problem. Want to boot MACRIUM rescue media (USB Flashdrive) to restore images. Want to boot standalone memtest86. However, only boots Win-10 install media flashdrive. No other program or OS will boot from Flash. Absolutely perplexed. Purchased $25 Flashdrive to test better quality (SAMSUNG FIT PLUS 64GB). Doesn't boot. Ports are good.. MACRIUM Flashdrives programmed on this PC boot fine on other PC's, just not this one. Need ideas - want to rely on recovery of disk images, and ability to boot other OS's for testing. Thank you!

[WAWood]

@Who-Knew 

This PC came with Win10 preloaded, right?  Therefore, it was probably loaded in UEFI mode using GPT formatting -- and thus it wants boot media formatted the same way.  Which is probably why it boots from Win10 media.

I am surprised that MR media does not boot.  I use that on all my PCs and have created boot media on every one of them, including PCs that were preloaded in UEFI mode using GPT.  The BIOS-MBR media will not boot on those PCs, but the MR media created on those PC will boot on them just fine.

Suggest you put this question to the MR forums -- as what you are doing should work.  They may have suggestions for how you can recreate the boot media to work properly.

Good Luck

[Who-Knew]

Thank you for your review and experience. Continued researching after last communication. Found one person who cleaned USB connectors to fix USB troubles. Complete power-down and battery removed. Alcohol swab on flat blade screwdriver with extreme care. Worked! Everything boots repeatedly, even from USB-3.0 Hub recently added as trial & error. 2 days good so far.

[WAWood]

@Who-Knew 

Wow -- that's good to know!  I never would have suspected dirty contacts.  Thanks for letting us all know about this.