## TargetFrameworkName for default app domain no longer defaults to null if not set ### Scope Edge ### Version Introduced 4.6 ### Source Analyzer Status Planned ### Change Description The TargetFrameworkName was previously null in the default app domain, unless it was explicitly set. Beginning in 4.6, the TargetFrameworkName property for the default app domain will have a default value derived from the TargetFrameworkAttribute (if one is present). Non-default app domains will continue to inherit their TargetFrameworkName from the default app domain (which will not default to null in 4.6) unless it is explicitly overridden. - [ ] Quirked - [ ] Build-time break ### Recommended Action Code should be updated to not depend on `AppDomainSetup.TargetFrameworkName` defaulting to null. If it is required that this property continue to evaluate to null, it can be explicitly set to that value. ### Affected APIs * `M:System.AppDomainSetup.get_TargetFrameworkName` ### Category Core [More information](https://msdn.microsoft.com/en-us/library/dn833125(v=vs.110).aspx#Core)