I have installed .net 4.5rc from http://msdn.microsoft.com/en-us/netframework/hh854779.aspx because I would like to use the new spatial features when developing with visual visual web developer 2010 express. But when I want to change the target framework to .net 4.5 in the project properties it is not there. I have checked the directory in C:\Windows\Microsoft.NET\Framework64 and can see that there is no v4.5 folder but the v4.0 directory has been updated with a timestamp corresponding to when I installed v4.5. The version of the v4.0 directory is v4.0.30319. I am running windows 7 on my computer. Any ideas why I cannot find v4.5 ? thanks Thomas *UPDATE Based on the comment below I have found out that I am running 4.5. For others reading this post, .net 4.5 replaces the files in the .net 4.0 directory but without renaming the directory to .net 4.5 (a bit confusing). To check whether your assemblies have been updated check the product version of eg. system.dll (right click - details). According to this post http://www.west-wind.com/weblog/posts/2012/Mar/13/NET-45-is-an-inplace-replacement-for-NET-40 if the product version is above 17000 it is running 4.5.