“…The necessary condition of existence of the integrals in (3.1) is B 0 (u), B 1 (u) ∈ L 2 (H; H) (the space of Hilbert-Schmidt operators acting in H) for any u ∈ H. It is not the case here, therefore it is impossible to obtain theorems on existence and uniqueness of solution (weak, or mild) for the problem (3.3) (see, for example, Theorem 6.7, p. 164 in [5], Theorem 3.3, p. 97 in [6]). The way out can be found in setting the problem in the space of generalized Hilbert-spacevalued random variables (S) −ρ (H) ⊃ L 2 (Ω, F, P ; H), ρ ∈ [0; 1] (see the definition and properties of this space in [9]).…”