SUO, Visual Studio Solution User Options File (.suo)
The SUO Developer file format
SUO files are created by Microsoft Visual Studio in order to store user information. The data gathered is stored in a binary and structured format. In Visual Studio, the SUO file is created by WriteUserOptions. In order to save changes, SaveUserOptions is used. Loading an already created SUO file can be done by using the LoadUserOptions method.
Technical details of SUO files
As mentioned above, SUO files store user data. This information is stored in streams. The name of a stream is, at the same time, also the key that is used in order to identify the information stored in an SUO file. SUO files are very specific to the machine and Visual Studio installation they were created with. Hence why there is almost no sense in sharing them with other developers, even when they use Microsoft Visual Studio. Furthermore, SUO files are altered every time an associated Visual Studio solution is used.