Q:

Facebook symbols not found for i386 architecture

I get the following error when trying to compile my project in xcode 4 (worked fine in xcode 3.x)
    Undefined symbols for architecture i386:
  "_OBJC_CLASS_$_FBSession", referenced from:
      objc-class-ref in View1Controls.o
  "_OBJC_CLASS_$_FBLoginDialog", referenced from:
      objc-class-ref in View1Controls.o
  "_OBJC_CLASS_$_FBRequest", referenced from:
      objc-class-ref in View1Controls.o
  "_OBJC_CLASS_$_FBStreamDialog", referenced from:
      objc-class-ref in View1Controls.o
ld: symbol(s) not found for architecture i386
collect2: ld returned 1 exit status

Can anyone explain whats wrong?  I'm sure I've correctly imported the header files..
Thanks,
Jack

A:

Assuming the libraries with these functions are included in the Xcode project, this error occurs when the libraries are not linked with the binary executable file. This can happen when upgrading an older project to a newer version of Xcode.
To fix it navigate to the project overview in Xcode. Click on the target. Click on Build Phases. Expand the "Link Binary With Libraries" list. If libraries are not listed, click the "+", and add the appropriate libraries. 

