Assuming you have a Sony desktop PC (and not a laptop), <a href="http://www.iomega.com/datahandler/servlet/dataprocess/driverlist?database=steerdown">here</a> is a link to the Iomega's internal zip drive Windows 98 software (See under "Additional Software").
What specific Sony model do you have?
As far as checking things on your end, as grybeard22 mentioned you may want to check internally to see that the cable is secure to the motherboard and to the drive.
Also - have you accessed BIOS to make sure the drive is detected/configured properly?
Let us know.
