Remove any originals from the scanner glass Error

I am using HP ScanJet 7650 Flatted Scanner also I am using Mac Operating system but I am receiving below error when I try to scan a slide or Negative. All error detail is given below so that you can understand original problem easily. Please tell me its solution urgent.
Remove any originals from the scanner glass. Ensure that your TMA is connected securely and positioned correctly. See your user’s manual or electronic help for more information about setting up you TMA.
OK
