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# Failed to apply periodic boundary conditions. Please check the Design volume

## Issue:

This error, "Failed to apply periodic boundary conditions. Please check the Design volume." came up when I was running the **Homogenize Unit Cell** block.

## Applies to:

* Simulation
* Homogenize Unit Cell

## Cause:

This error is occurring because there is an issue with the Design Volume input.

## Solution:

To avoid this issue, use the Bounding Box of the mesh being homogenized as the Design volume. This ensures there are no boundary condition errors.

## Keywords:

*lattice volume boundary design homogenize cell periodic unit simulate issue failed conditions*