When I want to set the image of an actor or a world, it returns the following error. Restarting Greenfoot didn't work
EDIT: This only happens in one scenario
Exception in thread "AWT-EventQueue-0" java.lang.IllegalArgumentException: Empty region! at javax.imageio.ImageReader.computeRegions(ImageReader.java:2689) at com.sun.imageio.plugins.wbmp.WBMPImageReader.read(WBMPImageReader.java:184) at javax.imageio.ImageIO.read(ImageIO.java:1422) at javax.imageio.ImageIO.read(ImageIO.java:1282) at greenfoot.gui.images.ImageLibList$ImageListEntry.loadPreview(ImageLibList.java:412) at greenfoot.gui.images.ImageLibList$ImageListEntry.<init>(ImageLibList.java:401) at greenfoot.gui.images.ImageLibList$ImageListEntry.<init>(ImageLibList.java:376) at greenfoot.gui.images.ImageLibList$ImageListEntry.<init>(ImageLibList.java:368) at greenfoot.gui.images.ImageLibList.setDirectory(ImageLibList.java:159) at greenfoot.gui.images.ImageLibList.<init>(ImageLibList.java:127) at greenfoot.gui.images.ImageLibFrame.buildUI(ImageLibFrame.java:193) at greenfoot.gui.images.ImageLibFrame.<init>(ImageLibFrame.java:142) at greenfoot.actions.SelectImageAction.actionPerformed(SelectImageAction.java:106) at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995) at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318) at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387) at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242) at javax.swing.AbstractButton.doClick(AbstractButton.java:357) at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:809) at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:850) at java.awt.Component.processMouseEvent(Component.java:6290) at javax.swing.JComponent.processMouseEvent(JComponent.java:3267) at java.awt.Component.processEvent(Component.java:6055) at java.awt.Container.processEvent(Container.java:2039) at java.awt.Component.dispatchEventImpl(Component.java:4653) at java.awt.Container.dispatchEventImpl(Container.java:2097) at java.awt.Component.dispatchEvent(Component.java:4481) at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4575) at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4236) at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4166) at java.awt.Container.dispatchEventImpl(Container.java:2083) at java.awt.Window.dispatchEventImpl(Window.java:2482) at java.awt.Component.dispatchEvent(Component.java:4481) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:648) at java.awt.EventQueue.access$000(EventQueue.java:84) at java.awt.EventQueue$1.run(EventQueue.java:607) at java.awt.EventQueue$1.run(EventQueue.java:605) at java.security.AccessController.doPrivileged(Native Method) at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87) at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98) at java.awt.EventQueue$2.run(EventQueue.java:621) at java.awt.EventQueue$2.run(EventQueue.java:619) at java.security.AccessController.doPrivileged(Native Method) at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87) at java.awt.EventQueue.dispatchEvent(EventQueue.java:618) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161) at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)