Senior Member
Hello all, I have a wierd problem. I am running windows 7 32bit, and every time that I reboot my pc one of my external usb hard drives its drive letter keeps changing. and its allways the same drive that keeps changing. can anyone please help, thank you very much


Extraordinary Member
Hi DTCZSR, As far as I am aware any external drives that are plugged in via a USB will always take the next available drive letter when the PC is restarted. I'm guessing that if several external storage devices are plugged in it must run to an order of priority, but what that is......

Some more info on what drive letters you are using and what the external drive changes from/to would be helpful.

Try assigning a drive letter for that drive. The assigned drive letters will be issued first and then the next available drive letters starting from C will be automatically issued for any other devices needing a letter assignment.

I've started assigning specific letters for specific devices a few years ago.
  • C - - -- - - OS Drive (Even if possible, don't even think about changing this one)
  • D - - -- - - Data Drive
  • E, F, G, H - Other Devices (These values change depending on the devices I have inserted at the time)
  • I, J, K, L - Card Reader
  • M, N - - - - BD/DVD Drives

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