Expires Caching

Hi, My hosting support has told me to implement this code in my website;

EXPIRES CACHING

<IfModule mod_expires.c> ExpiresActive On ExpiresByType image/jpg "access plus 1 year" ExpiresByType image/jpeg "access plus 1 year" ExpiresByType image/gif "access plus 1 year" ExpiresByType image/png "access plus 1 year" ExpiresByType text/css "access plus 1 day" ExpiresByType application/pdf "access plus 1 month" ExpiresByType text/x-javascript "access plus 1 day" ExpiresByType application/x-shockwave-flash "access plus 1 month" ExpiresByType image/x-icon "access plus 1 year" ExpiresDefault "access plus 2 days" </IfModule> I did it but a few students are getting a problem when they purchase a course and then they try to access. They find that the course has not change to "start course" and they can still purchase it again (the same course). After cleaning the cache of their browser they can access the course. I understand that that problem is coming from this code but I don't know what line should I delete or limit. Could you, please, help me? Thanks! Daniel