Get the person who the administrator is to allow it unless that person is you yourself, if that's the case try to login as 'administrator' and then have a look in internet settings in the control panel to see if it's being disallowed there
If it's not there then get into your internet and go to tools/settings then scroll down to the options/properties and go to plugin's and from there right click the flash plugin and click allow
Im not 100% sure but it should be something similar to this