The risk of material misstatement combined with detection risk has some interesting challenges when dealing with a very large company. Misstatements that could make or break a smaller company (ex, 3 million dollars) could very well be immaterial to Microsoft. This means that I’ll have to form a rather different type of plan to audit Microsoft than I would need for a small independent company. At any rate, let’s look at what areas of Microsoft pose great detection risk, using the SEC 10-k statements as our guide.
A global megacorporation like Microsoft has to deal with foreign currency risk all over the world. Microsoft does hedge a portion of these risks, though divisions often end up with a small extra gain or loss due to the exchange rates from a foreign currency. 

With all sorts of fluxing exchange rates, epically some of the more volatile ones Microsoft transacts in such as Bitcoin, I will have to plan for these exchange rates. I’ll have to know how Microsoft exchanges their currencies and at what rates, and obtain information on how these transactions are conducted.
When attempting to audit inventory, Microsoft has been moving to being more and more digital - cloud services don't have to worry about geographic location the same way physical inventory does, and some are impractical (if not outright impossible ) to determine. In addition, Microsoft treats sales of Windows to OEMs (companies that build computers with Windows already installed) and all product sales to multinational organizations as having been done in the United States, as there is no feasible way to tell which country Dell or HP is going to sell a specific copy of Windows in. 
This means I’ll have to investigate if this potential mislabeling of regions could cause a material misstatement. Are these sales of different value in different regions? Are these differences material to Microsoft? The idea of a product changing value because it crossed an imaginary line on a map might seem silly, but a worthless product in one region could be quite valuable in another (move water from a town by a lake to a desert town and watch its price skyrocket). But we’re dealing with digital items and Microsoft as already sold them to the OEM. Does this effect Microsoft?
Furthermore, Microsoft does not sort inventory of physical goods by region, instead they estimate the value of the inventory no matter where it's located into the traditional inventory accounts (Raw materials, Work in process, and Finished goods). All of this means that there is a rather high risk of material misstatement by Microsoft when it comes to determining exactly what region many of its products belong in. A $0.50 product in one region could be a $50 product in another, and Microsoft works all over the globe. Is an Xbox one in a factory in China still have the same value as one in the United States? Investigation will be necessary to determine if a material misstatement has occurred.
