This message means that you are trying to open an invalid file using the "Resume from file..." feature. When an EXR file cannot be read correctly, the rendering will be canceled.
- The EXR file is damaged or inaccessible.
- The EXR file was saved with different set of render elements.
- The EXR file was stored at a different resolution than the currently set output resolution.
- The EXR file that was saved was rendered with the Region/Crop option that was changed or disabled later.
- The EXR file was saved from interactive rendering.
- Rendering should be resumed only if the scene appearance did not change.
- Rendering can be resumed only from Corona EXR files saved using "Save CXR..." button, not from any regular EXR files.
- Rendering can be resumed only if rendering resolution, render elements, and Region/Crop parameters were not changed.
- If the EXR file was saved from interactive rendering, you must make sure that current render settings are identical to what was used during that interactive rendering. For example, if NVIDIA AI Denoiser was used for interactive rendering (it is enabled by default), you will have to disable "Use high quality filtering" option in the System tab before resuming rendering from that file, because mixing these two features is not possible. Generally, the "Resume from file..." option is intended for regular, non-interactive rendering.