[Pw_forum] nscf+lelfield -----> Wrong k-string? Error

[Mojtaba Mirseraji]

Dear Users

I perform lelfield=.true. option in PWSCF (only in nscf) for berry
calculations of polarization but unfortunately
" Wrong k-string? "
error is showed.

I do not know how to solve it
I have this error when I run this nscf input:

 &CONTROL
                 calculation = 'nscf' ,
                 restart_mode = 'from_scratch' ,
                 prefix= 'E',
                 tstress = .true. ,
                 tprnfor = .true. ,
                 outdir='?',
                 etot_conv_thr = 1.0E-6  ,
                 forc_conv_thr = 1.0D-6 ,
                 pseudo_dir = '?',
                 lelfield= .true. ,
                 lberry= .true. ,
                 gdir= 3 ,
                 nppstr= 25 ,
/
 &SYSTEM
                        ibrav = 0,
                      celldm(1)= ?,
                       nat = 5,
                       ntyp = 3,
                    ecutwfc = 80.0 ,
                    ecutrho = 800.0 ,
                  occupations = 'fixed' ,
/
 &ELECTRONS
                  conv_thr = 1.D-6 ,
                  diago_full_acc = .TRUE.,
                  efield_cart(1) = 0.0D0 ,
                  efield_cart(2) = 0.0D0 ,
                  efield_cart(3) = 0.00001D0 ,
/
ATOMIC_SPECIES
O     15.9994  ?.UPF
Ti    47.867      ?.UPF
Ba    137.327    ?.UPF
CELL_PARAMETERS {cubic}
1.00000000     0.00000000    0.0000000
0.00000000     1.00000000    0.0000000
0.00000000     0.00000000    1.0135088
ATOMIC_POSITIONS {alat}
O        0.000000000   0.500000000   0.497977245
O        0.500000000   0.000000000   0.497977245
O        0.500000000   0.500000000  -0.016512609
Ti       0.500000000   0.500000000   0.525300320
Ba       0.000000000   0.000000000   0.005257800
K_POINTS {automatic}
8  8  8   1   1   1



I have changed all numbers of this input file but this error appeared !!!!!

Regards

Mojtaba Mirseraji
Ph.D. Candidate
Theoretical Condensed Matter Physics
Arak Univ.
IRAN