We should have seen the subfolder under Junk.
Deleting the Junk folder should be OK, but a safer option would be to remove the account then add back.
Because this is a POP account you must backup your Inbox before removing the account.
Select the Inbox for sbcglobal.net 2.
Under Mailbox in the Menu bar, select Export Mailbox...
In addition, you need to export your Drafts and Sent folders.
Option 2) Copy the entirePOP- sbcglobal.net 2 to the Desktop. This contains a backup of your default folders.
Remove the account in Mail.
Be sure the POP- sbcglobal.net 2 is deleted in your User's Library/Mail as well.
Add the account back.
Most likely you have left message in the Inbox on the server. These will be duplicates you have previously downloaded. You can remove all but the newest messages that were not exported.
After you assign the folders for Drafts, Junk, Trash import your data from the folder on the Desktop.
Go to Mail's File menu and select "Import". Then choose "Mail for Mac OS X" and when asked for the location, select thePOP- sbcglobal.net 2 folder. Select your Inbox, Drafts and Sent folders.
These will show up under "On My Mac" under Import. You can then move the messages to the default folders.