I have edited your topic: most recent version of Captivate is 11.5, one of the releases of CP2019.
DId you buy an eternal license or a subscription license? If it is a subscription license, you should be allowed to have CP2017 as well, try to download it. For a perpetual license, contact the vendor. There is no way to open a project created with 11.5 in any version of 10.