Windows Forms Programming in Visual Basic .NET

Partially Trusted Assembly Considerations

As mentioned earlier in this chapter, by default .NET code deployed over the Web will be awarded a smaller set of permissions than code launched directly from the hard drive in the MyComputer zone. Any assembly, whether it's an .exe or a .dll, that's launched from the MyComputer zone will be fully trusted by default, and this means that it can do anything that the launching user is allowed to do. Assemblies deployed from the Web, on the other hand, will be partially trusted, because they aren't allowed to do everything. If you're building assemblies that are designed to work in a partially trusted environment, you need to take this into account, or else your users will see a lot of security exceptions. ...