Index: django/django/contrib/admin/widgets.py
===================================================================
--- django/django/contrib/admin/widgets.py	(revision 7968)
+++ django/django/contrib/admin/widgets.py	(working copy)
@@ -3,6 +3,7 @@
 """
 
 import copy
+import urllib
 
 from django import newforms as forms
 from django.newforms.widgets import RadioFieldRenderer
@@ -88,8 +89,8 @@
         from django.conf import settings
         output = []
         if value:
-            output.append('%s <a target="_blank" href="%s%s">%s</a> <br />%s ' % \
-                (_('Currently:'), settings.MEDIA_URL, value, value, _('Change:')))
+            output.append('%s <a target="_blank" href="%s">%s</a> <br />%s ' % \
+                (_('Currently:'), urllib.pathname2url('%s%s' % (settings.MEDIA_URL, value)), value, _('Change:')))
         output.append(super(AdminFileWidget, self).render(name, value, attrs))
         return mark_safe(u''.join(output))
 
Index: django/tests/regressiontests/admin_widgets/models.py
===================================================================
--- django/tests/regressiontests/admin_widgets/models.py	(revision 7968)
+++ django/tests/regressiontests/admin_widgets/models.py	(working copy)
@@ -50,6 +50,11 @@
 >>> print conditional_escape(w.render('test', 'test'))
 Currently: <a target="_blank" href="%(MEDIA_URL)stest">test</a> <br />Change: <input type="file" name="test" />
 
+In Windows, make sure that backward slashes are turned into forward slashes in the url.
+>>> w = AdminFileWidget()
+>>> print conditional_escape(w.render('testname', 'path\\\\file'))
+Currently: <a target="_blank" href="%(MEDIA_URL)spath/file">path\\file</a> <br />Change: <input type="file" name="testname" />
+
 >>> band = Band.objects.create(pk=1, name='Linkin Park')
 >>> album = band.album_set.create(name='Hybrid Theory')