We enumerate by computer algorithms all simple t (t +7, t +1, 2) designs for 1 t 5, i.e. for all possible t , and this enumeration is new for t 3. The number of nonisomorphic designs is equal to 3, 13, 27, 1 and 1 for t = 1, 2, 3, 4 and 5, respectively. We also present some properties of these designs including orders of their full automorphism groups and resolvability.