"using an external hard drive with a USB 2.0 connection to backup all my important documents."
This means to me this is a backup and not the only copy. If the only copy then where is the backup? That is, you did write backup and not "to store all my..."
The issue of USB powered drives is not unknown. Try adding a powered USB HUB or if your unit supports it, add a power supply to it.
If it is backup, then just delete the partition, create and format a new partition and begin again but keep an eye out for corruption. If it does corrupt then make it a warranty issue.
I recently started using an external hard drive with a USB 2.0 connection to backup all my important documents. The drive is USB powered and NTFS formatted.
On multiple occasions during file transfers the drive would 'hang' and explorer would become "Not responding" and I would be unable to "safely remove USB device", forcing me to turn off the PC or yank the USB cable out.
Now many of my documents and folders have become "corrupted" and unaccessible. Is there any way I could salvage that data or restore it?
I appreciate any advice...