# Airway Segmentation is working fine on sample CT but raises an error when running on my CT 

**URL:** <https://discourse.slicer.org/t/airway-segmentation-is-working-fine-on-sample-ct-but-raises-an-error-when-running-on-my-ct/30235>\
**Category:** Support\
**Tags:** segmentation, lung\
**Created:** [June 26, 2023, 2:55pm UTC](https://discourse.slicer.org/t/airway-segmentation-is-working-fine-on-sample-ct-but-raises-an-error-when-running-on-my-ct/30235 "2023-06-26T14:55:41Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Matteboo](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/matteboo/32/66548_2.png) [@Matteboo](https://discourse.slicer.org/u/Matteboo)\
**Post date:** [June 26, 2023, 2:55pm UTC](https://discourse.slicer.org/t/airway-segmentation-is-working-fine-on-sample-ct-but-raises-an-error-when-running-on-my-ct/30235/1 "2023-06-26T14:55:41Z")

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Hello,  
As I say in the title I’m using a toolbox (airway segmentation). When I use it on a CT from “Sample Data” the toolbox runs fine and give the appropriate results. However, when I try to run it on my CTs I have an error. (the program doesn’t finish and I don’t have a result)  
The error is **AttributeError: ‘NoneType’ object has no attribute ‘SetTag’** if that helps

Has anyone ever run into a similar issue ?  
Is there something I should check about my CTs ?  
Thank you in advance 😊

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**Author:** ![rbumm](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rbumm/32/9404_2.png) [@rbumm](https://discourse.slicer.org/u/rbumm)\
**Post date:** [June 26, 2023, 5:10pm UTC](https://discourse.slicer.org/t/airway-segmentation-is-working-fine-on-sample-ct-but-raises-an-error-when-running-on-my-ct/30235/2 "2023-06-26T17:10:27Z")

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Hello,

Which airway segmentation are you using?

This

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/d/8/d8fe363d6269f65ffa15e9c4231610ecbb77e6b2.png)

is unstable and has not been maintained for a long time.

Try the LungCTSegmenter from the LungCTAnalyzer package.  
It has an airway segmentation option.

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/7/e/7e868f10df6a2348da32398c9b3298c318fcdeb7.png)