There is a related thread. It is not about once this happens. A few tips to avoid issue.

1. Don't use undo
2. Don't explode exlode spaces or make a SketchUp Sketchup group or component combining multiple spaces.
3. Don't save the SketchUp file unless you need to. Opening the th OSM directly is more reliable.
4. Use SaveAs frequently so you have many OSM files you can roll back to.

Here is a link with tips once you suspect a probelm in a model

help-regarding-rendering-and-white-surfaces

There Here is a w related thread. It is not about once this happens. A few tips to avoid issue.

1. Don't use undo
2. Don't exlode spaces or make a Sketchup group or component combining multiple spaces.
3. Don't save the SketchUp file unless you need to. Opening th OSM directly is more reliable.
4. Use SaveAs frequently so you have many OSM files you can roll back to.

Here is a link with tips once you suspect a probelm in a model

help-regarding-rendering-and-white-surfaces

Here is w related thread. It is not about once this happens. A few tips to avoid issue.

1. Don't use undo
2. Don't exlode spaces or make a Sketchup group or component combining multiple spaces.
3. Don't save the sagr th SketchUp file unless you need to. Opening th OSM directly is more reliable.
4. Use SaveAs frequently so you have many OSM files you can roll back to.

Here is a link with tips once you suspect a probelm in a model

help-regarding-rendering-and-white-surfaces