cannot use old values as the initial values for new step

Dear sir or madam,

I am using comsol to simulate a stationary model. I had convergence problems so that I was forced to vary the inlet BCs gradually to converge to the real case and I had to use the last value of previous step as the initial value in the new step. But it was always 0 when I showed the initial values !!! I don't know what happend and could anybody help out, please ?

Thank you very much.
Best wishes