I had this problem in my previous laptop which didn't have enough storage
space so the arc was installed in an external hard drive. I thought maybe
that was causing the problem. So I installed arc in a new laptop (local
drive) wich meets the requirements for arc, according to the system
requirements checkup. Maybe I'll try reinsatalling version 10.3 if I can,
as its a students trail authorization.
Thanks anyway, Dan and everyone who responded to my post.