I just purchased Lightroom 3 and have install it. When first opening I received the following error message: "Lightroom encountered a problem when trying to update the format of the catalog file and cannot use this caralog in this version of Lightroom". Ideas?
Try starting Lightroom with a new catalog (hold down the ctrl key when starting Lightroom and choose "Create a new catalog" from the dialog that appears. Then, go to File > Open catalog and select the catalog from your previous version of Lightroom. If that doesn't work, you can try File > Import from Catalog.