Sql express 2008 r2 on asp.net 4 framework

I've a windows 2008 server and I've installed asp.net 4.0
I want to install Sql express R2 but cannot because It want 3.5 sp1 asp.net
I've found a sql express 2008 R2 version for asp.net 4.0 and I've installed it.
Now I'm searching Management studio tools for my version but I not found it.
All version is for asp.net 3.5!!!!
I'm very tired..
Can someone help me?
 
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