# I'm getting this error when I run an application

**URL:** https://openmc.discourse.group/t/im-getting-this-error-when-i-run-an-application/2643
**Category:** User Support
**Created:** [January 20, 2023, 7:29pm UTC](https://openmc.discourse.group/t/im-getting-this-error-when-i-run-an-application/2643 "2023-01-20T19:29:48Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![emilmammadzada](https://avatars.discourse-cdn.com/v4/letter/e/c4cdca/32.png) [@emilmammadzada](https://openmc.discourse.group/u/emilmammadzada)
#### Post date: [January 20, 2023, 7:29pm UTC](https://openmc.discourse.group/t/im-getting-this-error-when-i-run-an-application/2643/1 "2023-01-20T19:29:48Z")

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Reading materials XML file…  
Reading geometry XML file…  
Reading U238 from  
/home/emil/Downloads/endfb71/endfb-vii.1-hdf5/wmp/neutron/U238.h5  
HDF5-DIAG: Error detected in HDF5 (1.10.4) thread 139749681391552:  
#000: …/…/…/src/H5F.c line 509 in H5Fopen(): unable to open file  
major: File accessibilty  
minor: Unable to open file  
#001: …/…/…/src/H5Fint.c line 1400 in H5F\_\_open(): unable to open file  
major: File accessibilty  
minor: Unable to open file  
#002: …/…/…/src/H5Fint.c line 1546 in H5F\_open(): unable to open file: time = Fri Jan 20 20:23:29 2023  
, name = ‘/home/emil/Downloads/endfb71/endfb-vii.1-hdf5/wmp/neutron/U238.h5’, tent\_flags = 0  
major: File accessibilty  
minor: Unable to open file  
#003: …/…/…/src/H5FD.c line 734 in H5FD\_open(): open failed  
major: Virtual File Layer  
minor: Unable to initialize object  
#004: …/…/…/src/H5FDsec2.c line 346 in H5FD\_sec2\_open(): unable to open file: name = ‘/home/emil/Downloads/endfb71/endfb-vii.1-hdf5/wmp/neutron/U238.h5’, errno = 2, error message = ‘No such file or directory’, flags = 0, o\_flags = 0  
major: File accessibilty  
minor: Unable to open file  
ERROR: Failed to open HDF5 file with mode ‘r’:  
/home/emil/Downloads/endfb71/endfb-vii.1-hdf5/wmp/neutron/U238.h5

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### Author: ![paulromano](https://yyz2.discourse-cdn.com/free1/user_avatar/openmc.discourse.group/paulromano/32/486_2.png) [@paulromano](https://openmc.discourse.group/u/paulromano)
#### Post date: [January 28, 2023, 5:40pm UTC](https://openmc.discourse.group/t/im-getting-this-error-when-i-run-an-application/2643/2 "2023-01-28T17:40:07Z")

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> [@emilmammadzada](#):
>
> ‘/home/emil/Downloads/endfb71/endfb-vii.1-hdf5/wmp/neutron/U238.h5’, errno = 2, error message = ‘No such file or directory’, flags = 0, o\_flags = 0

It looks like it’s trying to open a file that doesn’t exist. It’s possible that your cross section library might have gotten extracted incorrectly. I would try clearing it out and extracting the tarball for the ENDF/B-VII.1 library again.