I recently purchased a Western Digital to put in my USB external enclosure to upgrade a smaller WD drive. The computer recognized the old drive but it didn't see the new drive. Any hints on what my problem is and what I have to do to correct it?
The most obvious thing to check is that you have reconnected everything securely - both the power and data connectors to the new drive.
The next thing to check is that the drive has the right jumper settings. You'll need to check these against the model of the drive.