Issue with WPS Single Domain Case - Ungrib using Online tutorial

[arungs]

While running WPS online tutrorial of single domain case from ARW Online Tutorial I am facing an error while using
./ungrib.exe

*** Starting program ungrib.exe ***
At line 133 of file read_namelist.f90 (unit = 10, file = 'namelist.wps')
Fortran runtime error: Cannot match namelist object name prefix

Error termination. Backtrace:
#0 0x7fb15791b3fd in finalize_transfer
at ../../../libgfortran/io/transfer.c:4305
#1 0x45dd91 in ???
#2 0x407f0b in ???
#3 0x4092bf in ???
#4 0x7fb156b3bd84 in ???
#5 0x402c9d in ???
#6 0xffffffffffffffff in ???


My WPS namelist file is as follows

&share
wrf_core = 'ARW',
max_dom = 1
start_date = '2016-10-06_00:00:00',
end_date = '2016-10-08_00:00:00',
interval_seconds = 21600,
prefix = 'FILE'
/

&geogrid
parent_id = 1, 1,
parent_grid_ratio = 1, 3,
i_parent_start = 1, 53,
j_parent_start = 1, 25,
e_we = 150, 220,
e_sn = 130, 214,
geog_data_res = 'default','default',
dx = 15000,
dy = 15000,
map_proj = 'lambert',
ref_lat = 33.00,
ref_lon = -79.00,
truelat1 = 30.0,
truelat2 = 60.0,
stand_lon = -79.0,
geog_data_path = '/glade/work/wrfhelp/WPS_GEOG/'
/

&ungrib
out_format = 'WPS',
prefix = 'FILE',
/

&metgrid
fg_name = 'FILE'
/

 

[arungs]

Solved (by just removing prefix = 'FILE' from &share session ) by Editing my WPS namelist file is as follows

&share
wrf_core = 'ARW',
max_dom = 1
start_date = '2016-10-06_00:00:00',
end_date = '2016-10-08_00:00:00',
interval_seconds = 21600,
/

&geogrid
parent_id = 1, 1,
parent_grid_ratio = 1, 3,
i_parent_start = 1, 53,
j_parent_start = 1, 25,
e_we = 150, 220,
e_sn = 130, 214,
geog_data_res = 'default','default',
dx = 15000,
dy = 15000,
map_proj = 'lambert',
ref_lat = 33.00,
ref_lon = -79.00,
truelat1 = 30.0,
truelat2 = 60.0,
stand_lon = -79.0,
geog_data_path = '/glade/work/wrfhelp/WPS_GEOG/'
/

&ungrib
out_format = 'WPS',
prefix = 'FILE',
/

&metgrid
fg_name = 'FILE'
/