Hi @KARENLINTON - I'm sorry you're having trouble printing. What is the error message you see? Is this a Mastery Connect item-based assessment or a document-based assessment?
Currently, some item-based tests are not printable if they contain Technology Enhanced Items (TEIs). However, if that is the case, you wouldn't see the Print icon instead of getting an error message. If the test is a document-based, try reloading or reuploading the document. You can also try regenerating the document if you open and view the assessment. 
Could there be an issue with your printer? Make sure you can print other things or other assessments. Let me know if you're still having trouble.
You can also contact our support team if needed. How do I create a Mastery Connect support ticket?
Best wishes,
Jen