If you use AsyncCtp With SL5, you could have the following issue: The type ‘System.Threading.Tasks.Task’ exists in both mscorlib.dll and AsyncCtpLibrary_Silverlight.dll.
So you can’t compile your project if you use Task class!
In this case, you could use an alias on the assembly but, you could not use async / await keywords.
I found a trick to do it: using two aliases on AsyncCtpLibrary_Silverlight. For this, in the aliases property of the assembly reference, I use “global,AsyncCtpLibrary” instead of only “global”.
Like this, I can use async/await because I have global alias on AsyncCtpLibrary_Silverlight.dll and I can use Task class with the following using:
extern alias AsyncCtpLibrary;
Note that if you use AsyncCtpLibrary_Silverlight5.dll instead of AsyncCtpLibrary_Silverlight.dll, you don’t need to do it!