diff --git a/IPython/frontend/terminal/interactiveshell.py b/IPython/frontend/terminal/interactiveshell.py
index a46c62d..862f2d4 100644
--- a/IPython/frontend/terminal/interactiveshell.py
+++ b/IPython/frontend/terminal/interactiveshell.py
@@ -458,7 +458,11 @@ class TerminalInteractiveShell(InteractiveShell):
         # code in an empty namespace, and we update *both* user_ns and
         # user_ns_hidden with this information.
         ns = {}
-        gui = pylab_activate(ns, gui, import_all)
+        try:
+            gui = pylab_activate(ns, gui, import_all)
+        except KeyError:
+            error("Backend %r not supported" % gui)
+            return
         self.user_ns.update(ns)
         self.user_ns_hidden.update(ns)
         # Now we must activate the gui pylab wants to use, and fix %run to take
diff --git a/IPython/lib/pylabtools.py b/IPython/lib/pylabtools.py
index ccafe44..8b25a8c 100644
--- a/IPython/lib/pylabtools.py
+++ b/IPython/lib/pylabtools.py
@@ -196,7 +196,7 @@ def find_gui_and_backend(gui=None):
 
     import matplotlib
 
-    if gui:
+    if gui and gui != 'auto':
         # select backend based on requested gui
         backend = backends[gui]
     else:
diff --git a/IPython/zmq/ipkernel.py b/IPython/zmq/ipkernel.py
index 6977d4a..2d138fd 100755
--- a/IPython/zmq/ipkernel.py
+++ b/IPython/zmq/ipkernel.py
@@ -740,8 +740,7 @@ class IPKernelApp(KernelApp, InteractiveShellApp):
         kernel_factory = Kernel
 
         if self.pylab:
-            key = None if self.pylab == 'auto' else self.pylab
-            gui, backend = pylabtools.find_gui_and_backend(key)
+            gui, backend = pylabtools.find_gui_and_backend(self.pylab)
 
         kernel = kernel_factory(config=self.config, session=self.session,
                                 shell_socket=self.shell_socket,
diff --git a/IPython/zmq/zmqshell.py b/IPython/zmq/zmqshell.py
index cb8f843..5c7d1c9 100644
--- a/IPython/zmq/zmqshell.py
+++ b/IPython/zmq/zmqshell.py
@@ -414,7 +414,12 @@ class ZMQInteractiveShell(InteractiveShell):
         from IPython.zmq.ipkernel import enable_gui
         opts, arg = self.parse_options(parameter_s, '')
         if arg=='': arg = None
-        return enable_gui(arg)
+        try:
+            enable_gui(arg)
+        except Exception as e:
+            # print simple error message, rather than traceback if we can't
+            # hook up the GUI
+            error(str(e))
 
     def enable_pylab(self, gui=None, import_all=True):
         """Activate pylab support at runtime.
@@ -440,13 +445,21 @@ class ZMQInteractiveShell(InteractiveShell):
         # code in an empty namespace, and we update *both* user_ns and
         # user_ns_hidden with this information.
         ns = {}
-        # override default to inline, from auto-detect
-        gui = pylabtools.pylab_activate(ns, gui or 'inline', import_all, self)
+        try:
+            gui = pylabtools.pylab_activate(ns, gui, import_all, self)
+        except KeyError:
+            error("Backend %r not supported" % gui)
+            return
         self.user_ns.update(ns)
         self.user_ns_hidden.update(ns)
         # Now we must activate the gui pylab wants to use, and fix %run to take
         # plot updates into account
-        enable_gui(gui)
+        try:
+            enable_gui(gui)
+        except Exception as e:
+            # print simple error message, rather than traceback if we can't
+            # hook up the GUI
+            error(str(e))
         self.magic_run = self._pylab_magic_run