You will find no free program able to play commercial BluRay disks because of patents, royalties etc. Check the software which came with your BluRay drive - retails units often come with e.g. PowerDVD which can play BluRays
Potplayer will only play unencrypted Blu-Rays, though it's great for DVDs. I've not found any good free software that can play encrypted Blu-Rays. Not sure there is one.
You will find no free program able to play commercial BluRay disks because of patents, royalties etc. Check the software which came with your BluRay drive - retails units often come with e.g. PowerDVD which can play BluRays