More robust VBoxManage error checking. [GH-1669]

CHANGELOG.md

@@ -1,6 +1,9 @@
 ## 1.2.3 (unreleased)
 
+IMPROVEMENTS:
 
+  - Better VBoxManage error detection on Windows systems. This avoids
+    some major issues where Vagrant would sometimes "lose" your VM. [GH-1669]
 
 ## 1.2.2 (April 23, 2013)
 

plugins/providers/virtualbox/driver/base.rb

@@ -303,7 +303,7 @@ module VagrantPlugins
               # Sometimes, VBoxManage fails but doesn't actual return a non-zero
               # exit code. For this we inspect the output and determine if an error
               # occurred.
-              if r.stderr =~ /VBoxManage: error:/
+              if r.stderr =~ /VBoxManage([.a-z]+?): error:/
                 @logger.info("VBoxManage error text found, assuming error.")
                 errored = true
               end