Simple answer yes...or at least should i have several external drives the only one i had issues with was one that runs on esata and i just had to manually update the driver for it to work,is your external usb 2/3 or esata? before you even start the upgrade go to your motherboard manufacturers site and check if its win 10 compatible and if so download all the drivers they have for windows 10 and save them on a thumb drive or storage drive in your system,if you bought a pre-built Pc then you need to do pretty much the same thing check to see if they have win 10 updates for your system and download them,windows 10 will install there own drivers for your hardware but ive found most of the drivers to be outdated/buggy so its best to be prepared to update your own system.