How to restore to personal profile?

Hi, I've just purchased and inserted additional RAM (2 x 2GB) to make 8GB total in my Dell XPS 8300. After power on the computer shows it recognised the 8GB RAM but when I logged on it has given me a temporary profile so I can't access my files etc. My username and admin profiles are offered at logon as before but then assigns the temporary profile. How do I get back my previous profile and access my files please?