Xamarin not building iOS project

Question

Everything was working fine up until today. It was working fine yesterday and I have not applied any changes since then. Today when I try to debug my project in Xamarin I get the only error:

/Library/Frameworks/Mono.framework/External/xbuild/Xamarin/iOS/Xamarin.iOS.Common.targets: Error: System.IO.FileNotFoundException: /Users/me/Dropbox/Projects/projectname/projectfile/obj/iPhone/Debug/build-ipad4.5-9.3.2/ibtool/Main.storyboardc/BYZ-38-t0r-view-78.nib does not exist
File name: '/Users/me/Dropbox/Projects/projectname/projectfile/obj/iPhone/Debug/build-ipad4.5-9.3.2/ibtool/Main.storyboardc/BYZ-38-t0r-view-78.nib'
  at System.IO.File.Copy (System.String sourceFileName, System.String destFileName, Boolean overwrite) <0x1a24c60 + 0x00333> in <filename unknown>:0 
  at Xamarin.MacDev.Tasks.SmartCopyTaskBase.CopyFile (System.String source, System.String target, System.String targetItemSpec) <0x3fc5de8 + 0x000c7> in <filename unknown>:0 
  at Xamarin.MacDev.Tasks.SmartCopyTaskBase.Execute () <0x3f08bf0 + 0x002bf> in <filename unknown>:0  (projectname)

Please note: I changed project name and my user name for the above example.

Answer 1

Renaming a viewcontroller caused me this problem

Removing the Obj & Bin folders manually present in the project solved me this problem.

Cleaning the project does not remove all the generated files