# Failed to detect end points: openSurfaceAtPoint failed: empty input polydata Error

**URL:** <https://discourse.slicer.org/t/failed-to-detect-end-points-opensurfaceatpoint-failed-empty-input-polydata-error/35029>\
**Category:** Support\
**Created:** [March 22, 2024, 8:40pm UTC](https://discourse.slicer.org/t/failed-to-detect-end-points-opensurfaceatpoint-failed-empty-input-polydata-error/35029 "2024-03-22T20:40:28Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![sthaker](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/sthaker/32/69192_2.png) [@sthaker](https://discourse.slicer.org/u/sthaker)\
**Post date:** [March 22, 2024, 8:40pm UTC](https://discourse.slicer.org/t/failed-to-detect-end-points-opensurfaceatpoint-failed-empty-input-polydata-error/35029/1 "2024-03-22T20:40:29Z")

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Hello,

I am uploading stl files of aortas as I normally do to extract centerlines using the “Extract Centerline” module. However, when I go to first set the endpoints, I get the error shown above. Nothing looks wrong with my STL, so I am confused where this error is possibly stemming from. I have done this countless times before, and I have never gotten this error.  
 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/9/d/9d22578e879c639a1e366bc7b6d86a6fdc089035.png)