diff --git a/scripts/installs/vm-guest-tools.bat b/scripts/installs/vm-guest-tools.bat
index 0be6782..387e7eb 100644
--- a/scripts/installs/vm-guest-tools.bat
+++ b/scripts/installs/vm-guest-tools.bat
@@ -28,12 +28,13 @@ goto :done
 
 :virtualbox
 
-:: There needs to be Oracle CA (Certificate Authority) certificates installed in order
-:: to prevent user intervention popups which will undermine a silent installation.
-cmd /c certutil -addstore -f "TrustedPublisher" A:\oracle-cert.cer
-
 move /Y C:\Users\vagrant\VBoxGuestAdditions.iso C:\Windows\Temp
 cmd /c ""C:\Program Files\7-Zip\7z.exe" x C:\Windows\Temp\VBoxGuestAdditions.iso -oC:\Windows\Temp\virtualbox"
+
+:: There needs to be Oracle CA (Certificate Authority) certificates installed in order
+:: to prevent user intervention popups which will undermine a silent installation.
+cmd /c certutil -addstore -f "TrustedPublisher" C:\Windows\Temp\virtualbox\cert\vbox-sha1.cer
+
 cmd /c C:\Windows\Temp\virtualbox\VBoxWindowsAdditions.exe /S
 goto :done