I would start with the Inventory Results report to see what failure types you are getting. You can generate that report by selecting the Environment scenario group and clicking on the Inventory Results tile. Once on the scenario detail page, click on generate report in the upper right. Reports are saved to the %My Documents%/MAP directory which you can open from the view menu in MAP.
The common failure types are listed in this TechNet Wiki article with explanations as to what they usually mean. For failures related to authentication, you can use WBEMTEST, which I've made a video tutorial on, to troubleshoot the connection faster. The instructions are found in this TechNet Wiki article.
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- Proposed as answer by Michael Switzer [MSFT CSG]Moderator Wednesday, October 23, 2013 9:25 PM