diff --git a/matlab/osr1.m b/matlab/osr1.m
index b73db2b244019944a09428b602a08d2136bb3256..2f9c65ec9871008780506aadbbde6cb58ee85266 100644
--- a/matlab/osr1.m
+++ b/matlab/osr1.m
@@ -126,7 +126,7 @@ elseif isequal(options_.osr.opt_algo,11)
 else
 
     if ~isempty(M_.osr.param_bounds) && ~(ismember(options_.osr.opt_algo,[1,2,5,9]) || ischar(options_.osr.opt_algo))
-        error('OSR: OSR with bounds on parameters requires a constrained optimizer, i.e. 1,2,5, or 9.')
+        error('OSR: OSR with bounds on parameters requires a constrained optimizer, i.e. opt_algo= 1,2,5, or 9.')
     end
     %%do actual optimization
     [p, f, exitflag] = dynare_minimize_objective(str2func('osr_obj'),t0,options_.osr.opt_algo,options_,M_.osr.param_bounds,cellstr(M_.param_names(i_params,:)),[],[], i_params,...