We study the occurrence of global gauge anomalies in the coset models of two-dimensional conformal field theory that are based on gauged WZW models. A complete classification of the non-anomalous theories for a wide family of gauged rigid adjoint or twisted-adjoint symmetries of WZW models is achieved with the help of Dynkin's classification of Lie subalgebras of simple Lie algebras.Considering each subgroup Z and the corresponding values of a 1 , a 2 ,ã 1 , andã 2 , and recalling the admissible values (3.33) of the level, we deduce Proposition 3.10 The twisted coset models corresponding to Lie algebra g = so(8), outer automorphism ω 4 and arbitrary subalgebra do not have anomalies for Z =Z (+ theory) and Z = Z 1 , Z 2 or Z diag . The models with h = g and Z =Z (-theory) is anomalous.The results for the twist ω −1 4 may be deduced from the above proposition if we observe that ω −1 4 may be obtained from ω 4 by the conjugation by any cyclic outer automorphism ω ′ of order 2. Hence the conditions for the absence or the presence of anomalies for the theory twisted by ω −1 4 are as for the ones for the twist ω 4 except for the exchange of the ± theories for Z =Z and k odd leading to Proposition 3.11 The twisted coset models corresponding to Lie algebra g = so(8), outer automorphism ω −1 4 and arbitrary subalgebra do not have anomalies for Z =Z ((−) k theory) and Z = Z 1 , Z 2 or Z diag . The models with h = g, and Z =Z ((−) k+1 theory) is anomalous.This may be confirmed by a direct calculation. 9