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Adaptive timestep less than 1 second

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Since WRF V3.6 it is apparently possible to use an adaptive timestep of less than 1 second.
I am using WRF ARW V4.2 and following the corresponding User Guide. I already used the same
namelist with a fixed time step without error, but with adaptive timestep I get at the beginning
taskid: 0 hostname: compute-2
module_io_quilt_old.F 2931 F
-------------- FATAL CALLED ---------------
ERROR reading namelist domains
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
The adaptive time stepping options I used in order to get start timesteps (seconds) 0.3, 0.1
and minima timesteps (seconds) 0.03, 0.01 are
 use_adaptive_time_step   = .true., .true.,
    step_to_output_time      = .true., .true.,
    target_cfl               = 1.2, 1.2,
    max_step_increase_pct    = 5, 51,
    starting_time_step       = 3, 1,
    starting_time_step_den   = 10, 10,
    max_time_step            = 45, 15,
    max_time_step_den        = 1,  1,
    min_time_step            = 3, 1,
    min_time_step_den        = 100, 100,
    adaptation_domain        = 1,
Am I misunderstanding how to define the parameters ?
Do you mind attaching your full error log (e.g., rsl.error.0000) and your full namelist.input file so that I can view those? To attach files, when in the text/editing screen, click on the tab below with 3 horizontal lines and then follow instructions. Is this error when running real.exe or wrf.exe? Thanks!
Thank you. After proceding step by step in my namelist I was able to overcome the problem. I guess some invisible character was in there. It is working.