diff --git a/src/gen_modules_clock.F90 b/src/gen_modules_clock.F90
index a64c704e4..99f861e0c 100755
--- a/src/gen_modules_clock.F90
+++ b/src/gen_modules_clock.F90
@@ -2,6 +2,8 @@ module g_clock
   !combining RT and Lars version
   !
   use g_config
+  use iso_fortran_env, only: error_unit
+  use mpi
   implicit none
   save
   real(kind=WP)            :: timeold, timenew     !time in a day, unit: sec
@@ -75,6 +77,9 @@ subroutine clock_init(partit)
     type(t_partit), intent(in), target    :: partit
     integer                               :: i, daystart, yearstart
     real(kind=WP)                         :: aux1, aux2, timestart
+    integer                               :: ierr
+    integer                               :: file_unit
+    character(512)                        :: errmsg
  
     ! the model initialized at
     timestart=timenew
@@ -82,10 +87,17 @@ subroutine clock_init(partit)
     yearstart=yearnew
 
     ! init clock for this run
-    open(99,file=trim(ResultPath)//trim(runid)//'.clock',status='old')
-    read(99,*) timeold, dayold, yearold
-    read(99,*) timenew, daynew, yearnew
-    close(99)
+    open(newunit=file_unit, file=trim(ResultPath)//trim(runid)//'.clock', action='read', &
+        status='old', iostat=ierr, iomsg=errmsg)
+    if (ierr /= 0) then
+      write (unit=error_unit, fmt='(3A)') &
+        '### error: can not open file ', trim(ResultPath)//trim(runid)//'.clock', &
+        ', error: ' // trim(errmsg)
+      call MPI_Abort(MPI_COMM_WORLD, 1, ierr)
+    end if
+    read(unit=file_unit, fmt=*) timeold, dayold, yearold
+    read(unit=file_unit, fmt=*) timenew, daynew, yearnew
+    close(unit=file_unit)
     if(daynew==0) daynew=1
     
     ! check if this is a restart or not
@@ -156,6 +168,9 @@ subroutine clock_finish
     real(kind=WP)            :: dum_timenew     !time in a day, unit: sec
     integer                  :: dum_daynew       !day in a year
     integer                  :: dum_yearnew     !year before and after time step
+    integer                               :: ierr
+    integer                               :: file_unit
+    character(512)                        :: errmsg
     
     dum_timenew = timenew
     dum_daynew  = daynew
@@ -166,10 +181,17 @@ subroutine clock_finish
        dum_yearnew=yearold+1
     endif
 
-    open(99,file=trim(ResultPath)//trim(runid)//'.clock',status='unknown')
-    write(99,*) timeold, dayold, yearold
-    write(99,*) dum_timenew, dum_daynew, dum_yearnew
-    close(99)
+    open(newunit=file_unit, file=trim(ResultPath)//trim(runid)//'.clock', action='write', &
+        status='unknown', iostat=ierr, iomsg=errmsg)
+    if (ierr /= 0) then
+      write (unit=error_unit, fmt='(3A)') &
+        '### error: can not open file ', trim(ResultPath)//trim(runid)//'.clock', &
+        ', error: ' // trim(errmsg)
+      call MPI_Abort(MPI_COMM_WORLD, 1, ierr)
+    end if
+    write(unit=file_unit, fmt=*) timeold, dayold, yearold
+    write(unit=file_unit, fmt=*) dum_timenew, dum_daynew, dum_yearnew
+    close(unit=file_unit)
   end subroutine clock_finish
   !
   !----------------------------------------------------------------------------
@@ -210,4 +232,4 @@ end subroutine is_fleapyr
   !
   !----------------------------------------------------------------------------
   !
-end module g_clock
+end module g_clock
\ No newline at end of file
diff --git a/src/oce_mesh.F90 b/src/oce_mesh.F90
index 1843e345b..0dba2f221 100755
--- a/src/oce_mesh.F90
+++ b/src/oce_mesh.F90
@@ -179,6 +179,7 @@ END SUBROUTINE mesh_setup
 ! Reads distributed mesh
 ! The mesh will be read only by 0 proc and broadcasted to the others.
 SUBROUTINE read_mesh(partit, mesh)
+use iso_fortran_env, only: error_unit
 USE o_PARAM
 USE g_CONFIG
 USE MOD_MESH
@@ -205,8 +206,10 @@ SUBROUTINE read_mesh(partit, mesh)
  integer, allocatable, dimension(:,:)       :: ibuff
  real(kind=WP), allocatable, dimension(:,:) :: rbuff
  integer, allocatable, dimension(:,:)       :: auxbuff ! will be used for reading aux3d.out 
- integer                                    :: fileunit, iostat
+ integer                                    :: fileunit
  character(32)                              :: mesh_checksum
+ integer                                    :: ioerr
+ character(512)                             :: errmsg
 
 #include "associate_part_def.h"
 #include "associate_mesh_def.h"
@@ -235,7 +238,14 @@ SUBROUTINE read_mesh(partit, mesh)
   if (mype==0) then
      file_name=trim(dist_mesh_dir)//'rpart.out'
      fileID=10
-     open(fileID, file=trim(file_name)) 
+     open(unit=fileID, file=trim(file_name), action='read', status='old', &
+         iostat=ioerr, iomsg=errmsg) 
+     if (ioerr /= 0) then
+       write (unit=error_unit, fmt='(3A)') &
+         '### error: can not open file ', file_name, &
+         ', error: ' // trim(errmsg)
+       call MPI_Abort(MPI_COMM_FESOM, 1, ierror)
+     end if
      allocate(partit%part(npes+1))
      part=>partit%part
      read(fileID,*) n
@@ -254,7 +264,7 @@ SUBROUTINE read_mesh(partit, mesh)
      write(*,*) n
      write(*,*) 'error: NPES does not coincide with that of the mesh'
      call par_ex(partit%MPI_COMM_FESOM, partit%mype, 1)
-     STOP
+     call MPI_Abort(MPI_COMM_FESOM, 1, ierror)
   end if
   ! broadcasting partitioning vector to the other procs
   if (mype/=0) then
@@ -2853,4 +2863,4 @@ subroutine check_total_volume(partit, mesh)
 end subroutine check_total_volume
 !
 !
-!_______________________________________________________________________________
+!_______________________________________________________________________________
\ No newline at end of file