error of tolerances

Hi,

I am working on an AC model. The frequency of my signal is 1.3e10 Hz.
I am specifying the time interval as (0, 0.1*T, 5*T)
and I get an error:

"Failed to find time step so that given tolerances are satisfied.
Time : 0
Last time step is not converged."

What might be the problem?

thanks

--
physics undergrad
loves photon.