diff --git a/all/golangconfig.py b/all/golangconfig.py
index cf57e0f..24d075f 100644
--- a/all/golangconfig.py
+++ b/all/golangconfig.py
@@ -15,8 +15,8 @@
     py2 = False
 
 
-__version__ = '1.0.0-beta'
-__version_info__ = (1, 0, 0, 'beta')
+__version__ = '0.9.0'
+__version_info__ = (0, 9, 0)
 
 
 # The sublime.platform() function will not be available in ST3 upon initial
@@ -45,6 +45,24 @@
     missing = None
 
 
+class GoRootNotFoundError(EnvironmentError):
+
+    """
+    An error occurred finding the $GOROOT on disk
+    """
+
+    directory = None
+
+
+class GoPathNotFoundError(EnvironmentError):
+
+    """
+    An error occurred finding one or more directories from $GOPATH on disk
+    """
+
+    directories = None
+
+
 class ExecutableError(EnvironmentError):
 
     """
@@ -119,6 +137,19 @@
             When one or more required_vars are not available. The .missing
             attribute will be a list of the names of missing environment
             variables.
+        golangconfig.GoPathNotFoundError
+            When one or more directories specified by the GOPATH environment
+            variable could not be found on disk. The .directories attribute will
+            be a list of the directories that could not be found.
+        golangconfig.GoRootNotFoundError
+            When the directory specified by GOROOT environment variable could
+            not be found on disk. The .directory attribute will be the path to
+            the directory that could not be found.
+
+        golangconfig.EnvVarError
+            When one or more required_vars are not available. The .missing
+            attribute will be a list of the names of missing environment
+            variables.
 
     :return:
         A two-element tuple.
@@ -245,6 +276,14 @@
             When the function is called from any thread but the UI thread
         TypeError
             When any of the parameters are of the wrong type
+        golangconfig.GoPathNotFoundError
+            When one or more directories specified by the GOPATH environment
+            variable could not be found on disk. The .directories attribute will
+            be a list of the directories that could not be found.
+        golangconfig.GoRootNotFoundError
+            When the directory specified by GOROOT environment variable could
+            not be found on disk. The .directory attribute will be the path to
+            the directory that could not be found.
 
     :return:
         A two-element tuple.
@@ -285,48 +324,51 @@
     if setting_name not in set(['GOPATH', 'GOROOT']):
         return (setting, source)
 
+    if setting is None and source is None:
+        return (setting, source)
+
     # We add some extra processing here for known settings to improve the
     # user experience, especially around debugging
-    is_str = isinstance(setting, str_cls)
-    if is_str:
+    _debug_unicode_string(setting_name, setting, source)
 
-        multiple_values = False
+    if not isinstance(setting, str_cls):
+        setting = str_cls(setting)
 
-        if setting_name == 'GOROOT':
-            if os.path.exists(setting):
-                return (setting, source)
+    if setting_name == 'GOROOT':
+        if os.path.exists(setting):
+            return (setting, source)
 
-        if setting_name == 'GOPATH':
-            values = setting.split(os.pathsep)
-            multiple_values = len(values) > 1
-            missing = False
+    has_multiple = False
+    if setting_name == 'GOPATH':
+        values = setting.split(os.pathsep)
+        has_multiple = len(values) > 1
+        missing = []
 
-            for value in values:
-                if not os.path.exists(value):
-                    missing = True
-                    break
+        for value in values:
+            if not os.path.exists(value):
+                missing.append(value)
 
-            if not missing:
-                return (setting, source)
+        if not missing:
+            return (setting, source)
 
-        if multiple_values:
-            value_desc = "one of the values"
-        else:
-            value_desc = "the value"
-        print(
-            'golangconfig: %s for %s from %s - "%s" - does not exist on the filesystem' %
-            (
-                value_desc,
-                setting_name,
-                source,
-                setting
-            )
-        )
+    if setting_name == 'GOROOT':
+        message = 'The GOROOT environment variable value "%s" does not exist on the filesystem'
+        e = GoRootNotFoundError(message % setting)
+        e.directory = setting
+        raise e
 
-    elif debug_enabled():
-        _debug_unicode_string(setting_name, setting, source)
+    if not has_multiple:
+        suffix = 'value "%s" does not exist on the filesystem' % missing[0]
+    elif len(missing) == 1:
+        suffix = 'contains the directory "%s" that does not exist on the filesystem' % missing[0]
+    else:
+        paths = ', '.join('"' + path + '"' for path in missing)
+        suffix = 'contains %s directories that do not exist on the filesystem: %s' % (len(missing), paths)
 
-    return (None, None)
+    message = 'The GOPATH environment variable ' + suffix
+    e = GoPathNotFoundError(message)
+    e.directories = missing
+    raise e
 
 
 def executable_path(executable_name, view=None, window=None):
diff --git a/dev/tests.py b/dev/tests.py
index 4d3cab4..d2344db 100644
--- a/dev/tests.py
+++ b/dev/tests.py
@@ -186,7 +186,7 @@
                 'go',
                 ['GOPATH', 'GOROOT'],
                 None,
-                golangconfig.EnvVarError
+                golangconfig.GoRootNotFoundError
             ),
         )
 
@@ -533,11 +533,9 @@
             'GOPATH': os.path.join(os.path.expanduser('~'), 'hdjsahkjzhkjzhiashs7hdsuybyusbguycas')
         }
         with GolangConfigMock(shell, env, None, None, {'debug': True}) as mock_context:
-            self.assertEquals(
-                (None, None),
+            def do_test():
                 golangconfig.setting_value('GOPATH', mock_context.view, mock_context.window)
-            )
-            self.assertTrue('does not exist on the filesystem' in sys.stdout.getvalue())
+            self.assertRaises(golangconfig.GoPathNotFoundError, do_test)
 
     def test_setting_value_multiple_gopath_one_not_existing(self):
         shell = '/bin/bash'
@@ -547,11 +545,10 @@
         with GolangConfigMock(shell, env, None, None, {'debug': True}) as mock_context:
             mock_context.replace_tempdir_env()
             mock_context.make_dirs(['usr/bin'])
-            self.assertEquals(
-                (None, None),
+
+            def do_test():
                 golangconfig.setting_value('GOPATH', mock_context.view, mock_context.window)
-            )
-            self.assertTrue('one of the values for GOPATH' in sys.stdout.getvalue())
+            self.assertRaises(golangconfig.GoPathNotFoundError, do_test)
 
     def test_setting_value_multiple_gopath(self):
         shell = '/bin/bash'
@@ -573,11 +570,9 @@
             'GOPATH': 1
         }
         with GolangConfigMock(shell, env, None, None, {'debug': True}) as mock_context:
-            self.assertEquals(
-                (None, None),
+            def do_test():
                 golangconfig.setting_value('GOPATH', mock_context.view, mock_context.window)
-            )
-            self.assertTrue('is not a string' in sys.stdout.getvalue())
+            self.assertRaises(golangconfig.GoPathNotFoundError, do_test)
 
     def test_subprocess_info_goroot_executable_not_inside(self):
         shell = '/bin/bash'
diff --git a/docs/changelog.md b/docs/changelog.md
index 015d74e..107a04d 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -1,5 +1,18 @@
 # golangconfig Changelog
 
-## 1.0.0
+## 0.9.0
+
+ - `subprocess_info()` and `setting_value()` will now raise
+   `GoRootNotFoundError()` when the `GOROOT` environment variable points to a
+   directory that could not be found on disk, and `GoPathNotFoundError()` when
+   one or more of the entries in the `GOPATH` environment variable could not be
+   found on disk.
+
+## 0.8.1
+
+ - Added support for GOPATH with multiple directories
+ - Fix an error when no project was open when using Sublime Text 3
+
+## 0.8.0
 
  - Initial release
diff --git a/docs/package_developer.md b/docs/package_developer.md
index faef4bb..0700132 100644
--- a/docs/package_developer.md
+++ b/docs/package_developer.md
@@ -84,6 +84,15 @@
 which is a list of all required environment variables that could not be
 found in the Sublime Text settings, or the shell environment.
 
+If the `GOROOT` environment variable points to a directory that does not exist
+on disk, the `golangconfig.GoRootNotFoundError()` will be raised. It has one
+attribute `.directory` that contains a unicode string of the `GOROOT` value.
+
+If one or more of the directories specified in the `GOPATH` environment variable
+can not be found on disk, the `golangconfig.GoPathNotFoundError()` will be
+raised. It has one attribute `.directories`, which is a list on unicode strings
+of the directories that could not be found.
+
 ### Requiring the Dependency
 
 When developing a package to utilize `golangconfig`, Package Control needs to be
@@ -116,11 +125,18 @@
 # coding: utf-8
 from __future__ import unicode_literals
 
+import sys
+
 import sublime
 import sublime_plugin
 
 import golangconfig
 
+if sys.version_info < (3,):
+    str_cls = unicode
+else:
+    str_cls = str
+
 
 class MyWindowCommand(sublime_plugin.WindowCommand):
     def run(self):
@@ -183,6 +199,23 @@
                     {'url': 'http://example.com/documentation'}
                 )
 
+        except (golangconfig.GoRootNotFoundError, golangconfig.GoPathNotFoundError) as e:
+            error_message = '''
+                My Package
+
+                %s.
+
+                Would you like to view the configuration documentation?
+            '''
+
+            prompt = error_message % str_cls(e)
+
+            if sublime.ok_cancel_dialog(prompt, 'Open Documentation'):
+                self.window.run_command(
+                    'open_url',
+                    {'url': 'http://example.com/documentation'}
+                )
+
 
 class MyTextCommand(sublime_plugin.TextCommand):
     def run(self):