diff --git a/src/browser/atom-application.coffee b/src/browser/atom-application.coffee
index 8f28cb726..ad854811e 100644
--- a/src/browser/atom-application.coffee
+++ b/src/browser/atom-application.coffee
@@ -60,6 +60,10 @@ class AtomApplication
 
   constructor: (options) ->
     {@resourcePath, @version, @devMode, @safeMode} = options
+
+    # Normalize to make sure drive letter case is consistent on Windows
+    @resourcePath = path.normalize(@resourcePath) if @resourcePath
+
     global.atomApplication = this
 
     @pidsToOpenWindows = {}
diff --git a/src/browser/main.coffee b/src/browser/main.coffee
index 514cea9fa..098a0a95d 100644
--- a/src/browser/main.coffee
+++ b/src/browser/main.coffee
@@ -55,6 +55,8 @@ start = ->
     console.log("App load time: #{Date.now() - global.shellStartTime}ms") unless args.test
 
 global.devResourcePath = process.env.ATOM_DEV_RESOURCE_PATH ? path.join(app.getHomeDir(), 'github', 'atom')
+# Normalize to make sure drive letter case is consistent on Windows
+globa.devResourcePath = path.normalize(global.devResourcePath) if global.devResourcePath
 
 setupCrashReporter = ->
   crashReporter.start(productName: 'Atom', companyName: 'GitHub')