# vtkXMLUnstructuredGridReader can not read binary vtu file correctly

**URL:** https://discourse.vtk.org/t/vtkxmlunstructuredgridreader-can-not-read-binary-vtu-file-correctly/15060
**Category:** Development
**Tags:** file-formats
**Created:** [December 23, 2024, 7:49am UTC](https://discourse.vtk.org/t/vtkxmlunstructuredgridreader-can-not-read-binary-vtu-file-correctly/15060 "2024-12-23T07:49:18Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![yiman](https://discourse.vtk.org/user_avatar/discourse.vtk.org/yiman/32/8716_2.png) [@yiman](https://discourse.vtk.org/u/yiman)
#### Post date: [December 23, 2024, 7:49am UTC](https://discourse.vtk.org/t/vtkxmlunstructuredgridreader-can-not-read-binary-vtu-file-correctly/15060/1 "2024-12-23T07:49:18Z")

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I have one vtu file, it has an “AppendedData” section, in this section, it contains the binary data of all cells. I can open this file without any error in paraview(I know this software also uses vtk), but If I try to read that file by using vtkXMLUnstructuredGridReader directly, it will failed. like this.

 ![image](https://discourse.vtk.org/uploads/default/original/2X/b/be17d5ab697d76477a34bd6da3e1271f5d8aae96.png)  
and the vtu file I used is here(I zipped the file)  
[step\_t0001.zip](https://discourse.vtk.org/uploads/short-url/5X4yKo7Z8PC4Dwi9ACD26lBFyvJ.zip) (2.3 MB)

Paraview version:5.11.1  
Vtk version: 9.2.0-pv5.11.0  
OS: Win 11

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### Author: ![jaswantp](https://discourse.vtk.org/user_avatar/discourse.vtk.org/jaswantp/32/10046_2.png) [@jaswantp](https://discourse.vtk.org/u/jaswantp)
#### Post date: [December 23, 2024, 3:20pm UTC](https://discourse.vtk.org/t/vtkxmlunstructuredgridreader-can-not-read-binary-vtu-file-correctly/15060/2 "2024-12-23T15:20:28Z")

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Hello, can you try a more recent version of VTK? Like 9.4.0?

Your file is readable and can be viewed in [VTK WebAssembly demos](https://kitware.github.io/vtk-wasm-demos/#/GeometryViewer?viewApi=webgl) which also uses vtkXMLUnstructuredGridReader

 ![image](https://discourse.vtk.org/uploads/default/original/2X/d/df397214e17b1e96f65b345fd24740ab34d71567.jpeg)

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<div class="post-metadata">

### Author: ![yiman](https://discourse.vtk.org/user_avatar/discourse.vtk.org/yiman/32/8716_2.png) [@yiman](https://discourse.vtk.org/u/yiman)
#### Post date: [December 24, 2024, 5:44am UTC](https://discourse.vtk.org/t/vtkxmlunstructuredgridreader-can-not-read-binary-vtu-file-correctly/15060/3 "2024-12-24T05:44:17Z")

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Thanks, I update vtk to version 9.3.0-pv5.12.1#5, then it works!