diff --git a/dnvm.ps1 b/dnvm.ps1
index f6c270875b..0861e08dff 100644
--- a/dnvm.ps1
+++ b/dnvm.ps1
@@ -67,7 +67,7 @@ function _WriteOut {
 
 ### Constants
 $ProductVersion="1.0.0"
-$BuildVersion="beta7-10400"
+$BuildVersion="beta7-10401"
 $Authors="Microsoft Open Technologies, Inc."
 
 # If the Version hasn't been replaced...
@@ -1115,7 +1115,7 @@ function dnvm-upgrade {
         [Parameter(Mandatory=$false)]
         [switch]$Unstable)
 
-    if($OS -ne "win") {
+    if($OS -ne "win" -and ![String]::IsNullOrEmpty($OS)) {
         #We could remove OS as an option from upgrade, but I want to take this opporunty to educate users about the difference between install and upgrade
         #It's possible we should just do install here instead.
          _WriteOut -ForegroundColor $ColorScheme.Error "You cannot upgrade to a non-windows runtime. Upgrade will download the latest version of the $RuntimeShortFriendlyName and also set it as your machines default. You cannot set the default $RuntimeShortFriendlyName to a non-windows version because you cannot use it to run an application. If you want to install a non-windows $RuntimeShortFriendlyName to package with your application then use 'dnvm install latest -OS:$OS' instead. Install will download the package but not set it as your default."
diff --git a/dnvm.sh b/dnvm.sh
index e05f783d8a..93f5d6a766 100644
--- a/dnvm.sh
+++ b/dnvm.sh
@@ -2,7 +2,7 @@
 # Source this file from your .bash-profile or script to use
 
 # "Constants"
-_DNVM_BUILDNUMBER="beta7-10400"
+_DNVM_BUILDNUMBER="beta7-10401"
 _DNVM_AUTHORS="Microsoft Open Technologies, Inc."
 _DNVM_RUNTIME_PACKAGE_NAME="dnx"
 _DNVM_RUNTIME_FRIENDLY_NAME=".NET Execution Environment"