Can't download the apps and permanent Ps file

I'm installing all the apps provided by my School, but all of them give me a continuous error. I've tried uninstalling all previous Adobe documents and apps by root, but the problem still persists.

Also, there's a Photoshop folder with the app half installed I've tried to erase several times but it just sticks. The trash tool from my Mac can't erase it since it says that it's in use, but there's no Ps program open.

I have a deadline tomorrow and I'm not gonna be able to finish it because of that, help please!