diff --git a/lib/cocoapods-ppbuild/helper/prebuild_sandbox.rb b/lib/cocoapods-ppbuild/helper/prebuild_sandbox.rb
index 8ebab75..6a93ee9 100644
--- a/lib/cocoapods-ppbuild/helper/prebuild_sandbox.rb
+++ b/lib/cocoapods-ppbuild/helper/prebuild_sandbox.rb
@@ -12,7 +12,7 @@ def self.replace_tagert_copy_source_sh(installer_context)
                     tn = "Pods-#{target.name}"
                     dir = Pathname.new(File.join(installer_context.sandbox.root,"Target Support Files", tn))
                     sh_path = File.join(dir, "#{tn}-resources.sh")
-                    if File.exists?(sh_path)
+                    if File.exist?(sh_path)
                         list.each do |tarname|
                             replace_content_file sh_path, tarname
                         end