Error message guide

Understand what error messages mean and view suggestions for resolving the error

We strive to make SmartSlice as robust as possible and are continuously improving its stability and its ability to work with increasingly complicated geometries. However, there are some known scenarios that SmartSlice is incompatible with and result in an error message. 

Presented here is a list of the most common error messages. Click an error message to view a description of the error and suggestions for resolving it. If you don't see your particular error message or would like help troubleshooting an error, please contact support.

The list of known errors and their resolutions is constantly changing as our team increases the robustness and functionality of SmartSlice! 

Chop voxelizer failed: [7011.1] Could not identify surface nodes for load or boundary condition with name :: Load number, Server returned error code 400

In most cases, this error means that the surface that was selected for the load or anchor is small relative to the size of the part. If the selected surface is too small, SmartSlice is unable to map the load or anchor to the meshed part. An example of a small surface is shown below.



  • Try a different surface Selection filter. There are 3 options: Flat, Concave, and Convex. For example, if the filter was set to Flat when you selected the surface, try Concave or Convex and see if more surfaces are selected.
  • If the STL mesh is too coarse (relatively large facets), try refining the STL mesh.
  • Select a larger surface.
  • Decrease the Line Width.

Chop voxelizer failed: [7014.1] Could not converge on a suitable voxel resolution, Server returned error code 400

SmartSlice uses the finite element method in order to simulate as-printed part performance and compute the factor of safety and maximum displacement. This requires a volume mesh of the part and the size of the "elements" in this mesh are dependent on the part size, the feature size, and the print settings. Some parts, particularly large parts with relatively small features, require a very large number of elements in order to capture the small details in the part. Such parts often exceed the maximum element count that can be supported by the cloud-based servers that SmartSlice runs on. In these cases, SmartSlice reports the error message above. 

In rare instances, the STL file is non-manifold and in these cases, this error is reported. Read this guide from Intructables for an overview of non-manifold geometry and how to fix it.


  • Increase the Line Width (affected by the Nozzle Diameter). Larger Line Widths typically correspond to larger elements and thus a reduction in the total element count.
  • Increase the Layer Height. We recommend increasing the Line Width before attempting to increase the Layer Height as the Line Width has more influence over the element size.
  • Defeature the part. Using a CAD program, remove any small feature (threads, fillets, holes, notches, text, etc.), especially features that do not have a significant contribution to the structural response of the part. The image below shows an example of a part that has been defeatured. In this example, the fillet, text, and the small cubic extrusion are not significant contributors to the structural response of the part and can be safely removed. By removing these small features, the element size for this part will increase and thus the total element count will decrease.


FEA analysis failed to deliver result: [4001.1] Extrusion unit cell - layer height to width ratio must be less than 0.9, Server returned error code 400

SmartSlice computes the as-printed material properties for various regions of the part and the Layer Height and Line Width are 2 print parameters that are key to computing these properties. The image below shows a cross-section of a printed region with the Layer Height and Line Width parameters identified. 

SmartSlice requires that the ratio of the Layer Height to the Line Width must be less than 0.9. This requirements is purely a practical requirement: It is not possible to extrude filament onto another surface and have the Layer Height be greater than the Line Width. 

The solution to this error is to simply adjust either the Layer Height or Line Width parameters to ensure that the LH/LW ratio is less than 0.9.


FEA analysis failed to deliver result: [5002.1] Solver factorization failed, Server returned error code 400

This error means that our cloud-based servers ran out of memory during the solution step of the Validate or Optimize procedure. Sometimes, this error occurs during an Optimization, even though the Validation for the model was successful.


The suggested remedies for this error are the same as the suggestions defined for this error. Namely, increase the Line Width, increase the Layer Height, and defeature the part.

Chop voxelizer failed: [7011.3] Overlapping surface with another load/fixed BC detected for BC with name :: Anchor number, Server returned error code 400

This error means that conflicting constraints were defined on a surface. For example, defining a load and an anchor on the same surface is a constraint conflict.


  • Do not define an anchor and a load on the same surface.
  • Upgrade the SmartSlice plugin to version 20.2 or greater. These versions have in-product warning messages that will detect this issue prior to submitting the Validation.
  • If you have upgraded to SmartSlice 20.2 or greater and this error message occurs, contact us.

Chop voxelizer failed: [7100.2] Cura Engine failed :: Requested extruder number 1 on setting name of setting does not exist, Server returned error code 400

For printers with multiple extruders, SmartSlice only supports extruder 1. Multi-material prints are not supported.


Make sure Extruder 1 is the active extruder and de-activate Extruder 2. This is simple to do in Cura. As shown in the video below:

  1. Click on the extruder toolbar.
  2. Select the 2nd extruder.
  3. De-select the Enabled box.

SmartSlice Server Error (400: Bad Request): 3mf cannot exceed 8 MB

The size of the Cura or Stratos 3mf file cannot exceed 8 MB. In most cases, 3mf files are much smaller than 8 MB. If your 3mf is larger than 8 MB, it is most likely due to an extremely refined STL mesh.


Generate an STL that uses a coarser mesh. There are a few methods to do this. Some CAD programs have an option that allows users to define the STL mesh refinement. Another method is to defeature the part and remove small features such as text and fillets prior to generating the STL. In general, small features increase the size of the STL mesh. 

We are sorry. Our servers appear to be struggling at the moment. We will look into it as soon as possible.

This message indicates that our servers have encountered an unidentified error. Our support team will automatically be notified when such an error occurs and will contact you once a resolution is identified. The team may contact you in order to get more details about your analysis in order to aid in the troubleshooting process.

Unable to contact SmartSlice servers!

Typically, this message means that your corporate firewall rules are blocking access to the cloud-based servers that run the SmartSlice solvers. Please refer to our Internet connection troubleshooting article for instructions to solve this issue.

Error while processing the job: [7012.3] Scan line does not begin or end on exterior polygon

This error is usually associated with a geometry issue or an issue with the Cura slicing engine. The suggested solution is to make a small change to one of the print settings. For example, changing the layer height or the number of walls.