New
#41
There's been so much said here that I've lost sight of whether there was anything on this old drive (which you're now connecting using the eBay purchased USB-to-IDE/SATA adapter to read through) is known usable right now?
Is there actually content you have on it that you want to salvage? Or do you just want to be able to use it as a brand new external drive (including one or more partitions)?
If you just want to use it as a new 3rd drive, and Windows says it is effectively unformatted, it either (a) is somehow "corrupted" in terms of its current file system and really does need to be formatted (to NTFS I would recommend) again which would make it completely empty but newly available, or (b) you should really just give it one more try to be usable "as-is".
The proper sequence of plug-ins for this type of external attachment would be to (1) plug in the data cable to the drive and to the adapter "heart", then (2) plug the USB cable into the adapter "heart", then (3) plug in the power cable to the the adapter "heart" and then (4) plug the power cable to the wall (so that the drive spins up and stabilizes), and then (5) plug the USB cable from the adapter "heart" into the PC which now makes the drive visible to Windows. This will result in "installing drivers" (for the USB adapter mechanism and externally visible drive), and a drive letter assigned (apparently you got H).
If its contents are still unrecognizable and "must be formatted first" still appears you can RUN Windows's own DISCMGMT.MSC to deal with FORMAT to NTFS in order to erase and format the drive as one large single partition. For maximum convenience and flexibility and partitioning needs (if you want to create multiple partitions on this drive, each one getting a drive letter) I would strongly recommend you use the highly recommended Minitool Partition Wizard (home FREE version or non-free PROFESSIONAL version). You will find Partition Wizard infinitely easier to use for your formatting and partitioning needs. Obviously Partition Wizard also works fine used just like DISKMGMT.MSC, to format/create just one partition on that drive... but I think you'll find its user interface easier and more intuitive.
==> Don't forget that anytime you want to remove a "removable device" (i.e. to pull the USB cable from your case first, only then powering down the drive second) that has been given a drive letter (like your new H hard drive) you must follow the well known standard SAFEFLY REMOVE HARDWARE procedure, to guarantee that all in-memory non-flushed data buffers (resulting from performance utilization methods of Windows that produces "write cache" data) are first written out to the drive before dropping the USB connection and removing the drive letter.