|i'm not sure if there isn't some confusion. I took it from the OP that the "adapter" was simply cables plugging in to the m/b providing eSATA connectors on a backplate. In that case there is no need for additional drivers.|
Note that eSATA is not (necessarily) plug and play. Don't plug the disk in whilst Windows is running. You should switch the computer off, plug in the drive, power it on, power on the computer, and check that it appears in the BIOS. Then start Windows and check Disk Management to see if the drive is listed and its partition recognized as an NTFS (or FAT32) partition. It may be that all you need to do is to assign a drive letter to the partition(s).