PLEASE HELP!

Hello,

I downloaded postgresql and when downloading at the end I got the following error message: "problem running post-install step. installation may not complete correctly. The database cluster initialization failed."

It looks like it download and it opens on my browser,  but I can't do anything. I am already over a week behind in school and this is horrible! I have un-installed and re-installed over 50 times. I have tried as admin, but when I get the following errors:

I looked everywhere on my computer and it looks like the only thing left behind is the folder, so I delete the folder before trying to re-install. 

I have tried re-installing with a different password, but when I finish downloading, I still get the same error, and it finishes downloading and when I sign in it still wants me to use my original password. Seeming as though it really isn't un-installing fully. I have even cleared my browser data, and still has the same issue. 

I have looked online and it seems like some people had this issue years ago, but all the help they had didn't work for me. 

Please help me. I am so beyond frustrated at this point.