There are many avenues for obtaining support and troubleshooting information for Office 365. Beyond the traditional support calls or emails to Microsoft, there are various forums and troubleshooting tools on the Internet. For Office 365, one of the best places to begin are the guided walkthroughs where you answer a series of questions about the issue(s) you are experiencing, and receive tips for solving specific problems. Some of these walkthroughs are targeted at administrators and some at end users.
One guide is the Office 365 Outlook connectivity guided walkthrough for administrators. It starts out by asking what type of mailbox is having problems and then gets into more specific troubleshooting scenarios depending upon the a answers you choose:
Another guide is the mail flow guided walkthrough for Office 365, which assists in troubleshooting issues where mail is not able to be sent or received:
The Lync Online guides have troubleshooting walkthroughs for both admins and end users:
These guides are a great starting point for helpdesk technicians, end users, and administrators alike. They are built around common questions and issues that Microsoft support has received over the years, and force you into good troubleshooting processes. They start with the “big picture” and may help you find that solutions to problems quicker than waiting for an official support request with Microsoft to run its course. I highly recommend them a starting point for troubleshooting for both IT novices and experts.