Old & new computers are both dell desktops with windows 10 with hard drives.
Thanks for contacting us! When using our Easy Transfer Cable, both the old and new computers must have working displays, mice/track pads, and keyboards in order to use the Easy Computer Sync file transfer software.
The software requires a product key to be entered on each computer, which is why both the display and keyboard are necessary.
After the product key is entered, you’ll need to click the “Next” button and choose a file transfer setting in order to access files for transfer on either computer.
If you’ve already purchased our cable, and you won’t be able to use it due to not having a monitor for your old computer, please feel free to request a return with Amazon.
Amazon usually processes refunds quickly. Please let us know with a reply back here if they give you any trouble at all.
And please contact us anytime if we can help in the future with this or any other Plugable brand product.