Xposed Installer Not Working

I'm trying to install the Xposed Framework, but every time I hit the install/update button, this comes up:

Does anyone know what this is? How do I fix it?

I'm new to softModding and stuff, so I don't know what's going on,

but I think the problem is probably because I went to install Xposed, realised that I didn't know what I was doing, canceled the installation halfway through, and then watched a tutorial that said just about exactly what I was going to do anyway. I downloaded the installer again, but when I tried to install Xposed this popped up. I've tried about 10 times since, but every time I do, this bloody box just pops up again, telling me that it can't create "/system/bin/app_process" because it already exists.

My phone is a Huawei Ascend Y330, if that helps.

Thanks!