There are a few possible causes for this message. A fault code would be helpful. Finisher fault codes on this product will be 312-xxx (x can be any number).
Andy
There's a problem with Xerox WorkCentre 7845 Main Tray is not available. User intervention is required to Power Off/On the machine; service is required if the problem persists. I tried rebooting it remotely and also doing an Image Overwrite remotely, but neither helped. Is a user guide available?