We installed 2.3 recently, and things were going relatively well. However, over the weekend the server host installed xcache on the machine, and caused some trouble.
First, the home page stopped showing up. This was resolved by removing the selected theme, and going back to the default theme.
The reason we had to remove the selected theme, instead of just changing it to default, is because two menu items in the wp-admin section also showed as blank: Plugins and Presentation.
Another 2.2x blog on the same server was still working fine.
Upon disabling xcache, the admin menus and other theme were working again.
Has anyone else experienced this, or know of a workaround to get the two to cooperate? The hos would like to have xcache running, and of course, we'd love to have wordpress running!
Help, and thanks!