Prolem with 6.5 thru 6.8

When I select any of these 4 lessons I am sent to a screen that says "The Website cannot Display the Page" This is an HTTP 500 error. I do not have this problem with any other lesson. I've tried ones in Chapter 7 and others in Chapter 6.1 thru 6.4 - they all are accessible except 6.5 - 6.8. Please tell me what I must do to see these 4 lessons Thank you

Salut Puma 115, we apologize for the problems you have had Are you still experiencing the same problem? We have recently created a new browser test which will let you know if you are missing any software, or need to upgrade current programs. Please try logging in again to run this test. The test will only run once. Please follow any advice given. If you continue to have problems please email to support@rocketlanguages.com. Thanks. Marie-Claire :)