diff --git a/src/calibre/gui2/__init__.py b/src/calibre/gui2/__init__.py
index 1828957232..2df4d0aa03 100644
--- a/src/calibre/gui2/__init__.py
+++ b/src/calibre/gui2/__init__.py
@@ -20,6 +20,7 @@ from calibre.utils.config import Config, ConfigProxy, dynamic, JSONConfig
 from calibre.ebooks.metadata import MetaInformation
 from calibre.utils.date import UNDEFINED_DATE
 from calibre.utils.localization import get_lang
+from calibre.utils.filenames import expanduser
 
 # Setup gprefs {{{
 gprefs = JSONConfig('gui')
@@ -598,7 +599,7 @@ def select_initial_dir(q):
         if os.path.exists(c):
             return c
         q = c
-    return os.path.expanduser('~')
+    return expanduser(u'~')
 
 class FileDialog(QObject):
     def __init__(self, title=_('Choose Files'),
@@ -608,7 +609,7 @@ class FileDialog(QObject):
                        modal=True,
                        name='',
                        mode=QFileDialog.ExistingFiles,
-                       default_dir='~',
+                       default_dir=u'~',
                        no_save_dir=False,
                        combine_file_and_saved_dir=False
                        ):
@@ -632,20 +633,20 @@ class FileDialog(QObject):
         if combine_file_and_saved_dir:
             bn = os.path.basename(default_dir)
             prev = dynamic.get(self.dialog_name,
-                    os.path.expanduser(u'~'))
+                    expanduser(u'~'))
             if os.path.exists(prev):
                 if os.path.isfile(prev):
                     prev = os.path.dirname(prev)
             else:
-                prev = os.path.expanduser(u'~')
+                prev = expanduser(u'~')
             initial_dir = os.path.join(prev, bn)
         elif no_save_dir:
-            initial_dir = os.path.expanduser(default_dir)
+            initial_dir = expanduser(default_dir)
         else:
             initial_dir = dynamic.get(self.dialog_name,
-                    os.path.expanduser(default_dir))
+                    expanduser(default_dir))
         if not isinstance(initial_dir, basestring):
-            initial_dir = os.path.expanduser(default_dir)
+            initial_dir = expanduser(default_dir)
         if not initial_dir or (not os.path.exists(initial_dir) and not (
                 mode == QFileDialog.AnyFile and (no_save_dir or combine_file_and_saved_dir))):
             initial_dir = select_initial_dir(initial_dir)
diff --git a/src/calibre/utils/filenames.py b/src/calibre/utils/filenames.py
index e9a589fe8a..959be49c8d 100644
--- a/src/calibre/utils/filenames.py
+++ b/src/calibre/utils/filenames.py
@@ -489,4 +489,18 @@ def remove_dir_if_empty(path, ignore_metadata_caches=False):
             return
         raise
 
-
+if iswindows:
+    # Python's expanduser is broken for non-ASCII usernames
+    def expanduser(path):
+        if isinstance(path, bytes):
+            path = path.decode(filesystem_encoding)
+        if path[:1] != u'~':
+            return path
+        i, n = 1, len(path)
+        while i < n and path[i] not in u'/\\':
+            i += 1
+        from win32com.shell import shell, shellcon
+        userhome = shell.SHGetFolderPath(0, shellcon.CSIDL_PROFILE, None, 0)
+        return userhome + path[i:]
+else:
+    expanduser = os.path.expanduser