Invalid Titanium SDK "3.5.1.GA"

Hi, i am new to Titanium, now i am using titanium sdk 4.0. This error came out when i building my apps:

[ERROR] : Invalid selected Titanium SDK "3.5.1.GA" Did you mean this? TRACE | titanium exited with exit code 1

I try to change the version name in tiapp.xml but to 3.5.1.GA but it still not working. Is there any way to solve this problem? Appreciate your help, thanks!