diff --git a/core/exclude.py b/core/exclude.py
index eb8ffc08..557ac823 100644
--- a/core/exclude.py
+++ b/core/exclude.py
@@ -12,6 +12,7 @@ from os import sep
 import logging
 import functools
 from hscommon.util import FileOrPath
+from hscommon.plat import ISWINDOWS
 import time
 
 default_regexes = [r"^thumbs\.db$",  # Obsolete after WindowsXP
@@ -19,10 +20,10 @@ default_regexes = [r"^thumbs\.db$",  # Obsolete after WindowsXP
                    r"^\.DS_Store$",  # MacOS metadata
                    r"^\.Trash\-.*",  # Linux trash directories
                    r"^\$Recycle\.Bin$",  # Windows
-                   r"^\..*",  # Hidden files
+                   r"^\..*",  # Hidden files on Unix-like
                    ]
 # These are too broad
-forbidden_regexes = [r".*", r"\/.*", r".*\/.*", r".*\..*"]
+forbidden_regexes = [r".*", r"\/.*", r".*\/.*", r".*\\\\.*", r".*\..*"]
 
 
 def timer(func):
@@ -168,10 +169,16 @@ class ExcludeList(Markable):
 
     def build_compiled_caches(self, union=False):
         if not union:
-            self._cached_compiled_files =\
-                [x for x in self._excluded_compiled if sep not in x.pattern]
-            self._cached_compiled_paths =\
-                [x for x in self._excluded_compiled if sep in x.pattern]
+            if not ISWINDOWS:
+                self._cached_compiled_files =\
+                    [x for x in self._excluded_compiled if not has_sep(x.pattern)]
+                self._cached_compiled_paths =\
+                    [x for x in self._excluded_compiled if has_sep(x.pattern)]
+            else:
+                self._cached_compiled_files =\
+                    [x for x in self._excluded_compiled if not has_sep(x.pattern)]
+                self._cached_compiled_paths =\
+                    [x for x in self._excluded_compiled if has_sep(x.pattern)]
             return
         marked_count = [x for marked, x in self if marked]
         # If there is no item, the compiled Pattern will be '' and match everything!
@@ -184,13 +191,13 @@ class ExcludeList(Markable):
             # the same regardless of whether the client asked for union or not
             self._cached_compiled_union_all =\
                 (re.compile('|'.join(marked_count)),)
-            files_marked = [x for x in marked_count if sep not in x]
+            files_marked = [x for x in marked_count if not has_sep(x)]
             if not files_marked:
                 self._cached_compiled_union_files = tuple()
             else:
                 self._cached_compiled_union_files =\
                     (re.compile('|'.join(files_marked)),)
-            paths_marked = [x for x in marked_count if sep in x]
+            paths_marked = [x for x in marked_count if has_sep(x)]
             if not paths_marked:
                 self._cached_compiled_union_paths = tuple()
             else:
@@ -488,3 +495,11 @@ def ordered_keys(_dict):
     list_of_items.sort(key=lambda x: x[1].get("index"))
     for item in list_of_items:
         yield item[0]
+
+
+if ISWINDOWS:
+    def has_sep(x):
+        return '\\' + sep in x
+else:
+    def has_sep(x):
+        return sep in x
diff --git a/core/tests/directories_test.py b/core/tests/directories_test.py
index 061e1476..8a5ddcdb 100644
--- a/core/tests/directories_test.py
+++ b/core/tests/directories_test.py
@@ -12,6 +12,7 @@ import shutil
 from pytest import raises
 from hscommon.path import Path
 from hscommon.testutil import eq_
+from hscommon.plat import ISWINDOWS
 
 from ..fs import File
 from ..directories import (
@@ -428,7 +429,10 @@ files: {self.d._exclude_list.compiled_files} all: {self.d._exclude_list.compiled
         assert "unwanted_subdirfile.gif" not in files
         assert "unwanted_subdarfile.png" not in files
 
-        regex3 = r".*Recycle\.Bin\/.*unwanted.*subdirfile.*"
+        if ISWINDOWS:
+            regex3 = r".*Recycle\.Bin\\.*unwanted.*subdirfile.*"
+        else:
+            regex3 = r".*Recycle\.Bin\/.*unwanted.*subdirfile.*"
         self.d._exclude_list.rename(regex2, regex3)
         assert self.d._exclude_list.error(regex3) is None
         # print(f"get_folders(): {[x for x in self.d.get_folders()]}")
@@ -516,6 +520,8 @@ files: {self.d._exclude_list.compiled_files} all: {self.d._exclude_list.compiled
         self.d.set_state(p1["foobar"][".hidden_dir"], DirectoryState.Normal)
         # The files should still be filtered
         files = self.get_files_and_expect_num_result(1)
+        eq_(len(self.d._exclude_list.compiled_paths), 0)
+        eq_(len(self.d._exclude_list.compiled_files), 1)
         assert ".hidden_file.txt" not in files
         assert ".hidden_subfile.png" not in files
         assert "foobar.jpg" in files
diff --git a/core/tests/exclude_test.py b/core/tests/exclude_test.py
index 3745ac21..8bfc8cc7 100644
--- a/core/tests/exclude_test.py
+++ b/core/tests/exclude_test.py
@@ -245,7 +245,7 @@ class TestCaseCompiledList():
             assert expr.pattern in exprs
 
     def test_compiled_files(self):
-        # test is separator is indeed checked properly to yield the output
+        # is path separator checked properly to yield the output
         regex1 = r"test/one/sub"
         self.e_separate.add(regex1)
         self.e_separate.mark(regex1)