By default, the initial guess of the nonlinear multiharmonic solver is a zero initial condition. You can specify an initial guess by issuing HBMOPT,UINIT. Example 3: Two Jointed Beams with Frictional Contact Interface shows how to define the initial solution vector from a previous analysis. It can come from any type of analysis, for example a static analysis or a previous HBM run. This procedure is particularly useful if a first HBM analysis fails to converge. A second one can be solved using one of the solution points as the initial guess and changing the solution controls or number of harmonics to achieve convergence.