Photoshop HELP! Really easy probably!

I cant for the life of me figure out how to change this from blue to another colour.
Please help and/or explain how to do this. Its winding me up.
file – http://~ Dead file host ~/files/243356061/sdicon.psd
Answer #1
Tried to open in PS7 and CS3 and it says it’s not a valid Photoshop document.