virtualbox.org

I installed Virtual Box on OSX host running Windowx XP as a Guest system. It worked for a long time. Suddebly, today the application (GUI) doesn't start. I reinstalled it but no chance.

You might want to print the following steps, or save them in a test file on your desktop, because there are a couple of reboots, and you don't want to go "hunting" in the forums...

1. Download the latest release, or the latest test build (NOT the development snapshot), if you don't already have them.
2. Reboot.
3. Make sure you're part of the "admin" group. If you are logged in with the primary user account/owner, you are part of the admin group.
4. Mount the DMG from the previous step. Run "VirtualBox_Uninstall.tool". Make sure there are no error messages. If there are, please post them, exactly as they appear.
5. Reboot.
6. Mount the DMG from the previous steps. Double-click the "VirtualBox.pkg". As soon as you start the installation, press "Cmd+L" to show the log. Select "Show All Logs" from the drop-down menu. Before the last step of the installation (Done), click the "Save" in the log window. ZIP and attach that file.
7. Start VirtualBox. If it crashes, open "Console.app" and look at "~/Library/Logs". Is there a VirtualBox related log with the current date/time? ZIP and attach that file as well.