The decay $b\to s\gamma$ and the charged Higgs boson mass without R-Parity

The experimental measurement of $B(b \to s\gamma)$ imposes important constraints on the charged Higgs boson mass in the MSSM. We show that by adding bilinear R--Parity violation (BRpV) in the tau sector, these bounds are relaxed. The bound on $m_{H^{\pm}}$ in the MSSM--BRpV model is $\gsim 200-250$ GeV for the the heavy squark limit. For lighter squarks, light charged Higgs bosons can be reconciled with $B(b \to s\gamma)$ only if there is also a light chargino. In the BRpV model if we impose $m_{\chi^{\pm}_1}>90$ GeV $m_{H^{\pm}} bosons would be observable at LEP II. The relaxation of the bounds is due mainly to the fact that charged Higgs bosons mix with staus and they contribute importantly to $B(b \to s\gamma)$.