Microsoft has released an Office 365 Troubleshooting tool here: http://community.office365.com/en-us/p/troubleshooting.aspx This tool asks a serious of questions to help isolate the problem you are having and then will provided suggested solutions. Nice to see Microsoft creating tools like this to help companies that are using their Cloud Services. This tool is FREE and can is flexible. Another nice feature is the first question asks whether it is a user or administration problem, so it can targeted for specific end user or administrative problems.