问题
As mentioned in the title, I have 
ReactiveCocoa/RACEXTScope.h file not found error in Prefix.pch file.
The following is Pod file
platform :ios, "7.1"
pod 'Parse-iOS-SDK', '~> 1.2'
pod 'ReactiveCocoa', '~> 2.3'
pod 'ReactiveViewModel', '~> 0.2'
pod 'Parse-RACExtensions', '~> 0.0'
pod 'CKCalendar', '~> 1.0'
pod 'SDWebImage', '~> 3.6'
As you can see from images, the file exists. But there is not interface declaration in the file. Does that matter?
I'm using Xcode 6.0.1
Can anyone give me a suggestion?
    回答1:
I had the same problem.
At the top of your podfile write this line:
link_with  ['ProjectName', 'ProjectNameTests']
install pod, and at your project Build Setting->Other Linker Flags, add $(inherited).
That happened because Tests couldn't find pods.
回答2:
solution for me was replace in podfile string     pod 'ReactiveCocoa', '~> 2.3'     with    pod 'ReactiveCocoa', '~> 2.3.1'
because in cocoapods.org not updated info http://i.stack.imgur.com/dWznK.png
回答3:
I had the same problem and fixed it.
In XCode go to the Build Settings -> search Header Search Paths and change the ${PODS_ROOT}/Headers/Public/ReactiveCocoa to recursive from non-recursive.
https://i.stack.imgur.com/Y04YY.png
来源:https://stackoverflow.com/questions/25970560/prefix-pch-reactivecocoa-racextscope-h-file-not-found-error