For three years, I have maintained a troubleshooting article here which provides a short summary listing of the articles available here which you can use to work through most pressing or urgent problems with Macs. For a number of reasons, I have moved this information from that article to a page. You can now access it either through that original article, which remains pinned to the top of this blog for ease of access, or through the Mac Troubleshooting Summary item in the list of Quick Links at the top right of each page. I hope this makes it both easier to access, and for me to keep it up to date.