Why use "CoCreateGuid" function from "OLE32.dll" when you can directly use "UuidCreate" function and only link against "Rpcrt4.dll"?
MSDN says that "CoCreateGuid" just wraps the return value of "UuidCreate" to a "HRESULT" so please avoid the overhead of this indirection.
For performance reasons (when generating multiple GUIDs) and when the GUID generated is only used locally on your machine you may also consider using "UuidCreateSequential" function.
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