diff --git a/README.md b/README.md
index be05b9e2..114d2d35 100644
--- a/README.md
+++ b/README.md
@@ -62,7 +62,7 @@ See the [Examples-README.md](examples/Examples-README.md) file.
 - Supported examples are listed in the [Examples-README.md](examples/Examples-README.md) file
 - Documentation is in the [docs/](docs) directory:
   - [Build instructions](docs/Build-instructions.md)
-  - [Knowledge base](docs/Knowledge-Base.md)
+  - [Knowledge Base](docs/Knowledge-Base.md)
   - [Migration guide](docs/Migration-guide.md)
   - [Tutorial](docs/Tutorial.md)
 - API reference is in the [api/](api) directory:
@@ -155,8 +155,8 @@ directly.
 - [Tutorial](docs/Tutorial.md)
 
 
-### API categories
-
+### API categories
+
 #### Modules
 
  * [cefpython](api/cefpython.md#cefpython) module
@@ -211,9 +211,9 @@ directly.
  * [StringVisitor](api/StringVisitor.md#stringvisitor-interface) interface
  * [WebRequestClient](api/WebRequestClient.md#webrequestclient-interface) interface
 
-
-### API index
-
+
+### API index
+
 * [Application settings](api/ApplicationSettings.md#application-settings)
   * [accept_language_list](api/ApplicationSettings.md#accept_language_list)
   * [auto_zooming](api/ApplicationSettings.md#auto_zooming)
diff --git a/src/compile_time_constants.pxi b/src/compile_time_constants.pxi
index 35f85002..632aab59 100644
--- a/src/compile_time_constants.pxi
+++ b/src/compile_time_constants.pxi
@@ -1,3 +1,3 @@
 # This file was generated by setup.py
-DEF UNAME_SYSNAME = "Linux"
-DEF PY_MAJOR_VERSION = 2
+DEF UNAME_SYSNAME = "Windows"
+DEF PY_MAJOR_VERSION = 3
diff --git a/tools/build.py b/tools/build.py
index 1d32dcf1..3e4f0f8b 100644
--- a/tools/build.py
+++ b/tools/build.py
@@ -879,7 +879,12 @@ def delete_directory_reliably(adir):
     print("[build.py] Delete directory: {dir}"
           .format(dir=adir.replace(ROOT_DIR, "")))
     if WINDOWS:
-        shutil.rmtree(adir)
+        # rmtree is vulnerable to race conditions. Sometimes
+        # deleting directory fails with error:
+        # >> OSError: [WinError 145] The directory is not empty:
+        # >> 'C:\\github\\cefpython\\build\\cefpython3_56.2_win64\\build\\
+        # >> lib\\cefpython3'
+        shutil.rmtree(adir, ignore_errors=True)
     else:
         # On Linux sudo might be required to delete directory, as this
         # might be a setup installer directory with package installed
diff --git a/tools/build_distrib.py b/tools/build_distrib.py
index 7466caf8..f2635df2 100644
--- a/tools/build_distrib.py
+++ b/tools/build_distrib.py
@@ -44,7 +44,8 @@
 7. Reduce packages size (Issue #321). After packing prebuilt binaries,
    reduce its size so that packages will use the reduced prebuilt binaries.
 8. Build cefpython modules for all supported Python versions on both
-   32-bit and 64-bit
+   32-bit and 64-bit. Backup and restore subprocess executable on Windows
+   built with Python 2.7 (Issue #342).
 9. Make setup installers and pack them to zip (Win/Mac) or .tar.gz (Linux)
 10. Make wheel packages
 11. Move setup and wheel packages to the build/distrib/ directory
@@ -129,7 +130,8 @@ def main():
             reduce_package_size_issue_262("64bit")
         remove_unnecessary_package_files("64bit")
     if not NO_REBUILD:
-        build_cefpython_modules(pythons_32bit + pythons_64bit)
+        build_cefpython_modules(pythons_32bit, "32bit")
+        build_cefpython_modules(pythons_64bit, "64bit")
     if pythons_32bit:
         make_packages(pythons_32bit[0], "32bit")
     if pythons_64bit:
@@ -439,7 +441,7 @@ def remove_unnecessary_package_files(arch):
     delete_cef_sample_apps(caller_script=__file__, bin_dir=bin_dir)
 
 
-def build_cefpython_modules(pythons):
+def build_cefpython_modules(pythons, arch):
     for python in pythons:
         print("[build_distrib.py] Build cefpython module for {python_name}"
               .format(python_name=python["name"]))
@@ -461,14 +463,62 @@ def build_cefpython_modules(pythons):
             sys.exit(1)
         print("[build_distrib.py] Built successfully cefpython module for"
               " {python_name}".format(python_name=python["name"]))
-    print("[build_distrib.py] Successfully built cefpython modules for"
-          " all Python versions")
+        # Issue #342
+        backup_subprocess_executable_issue342(python)
+
+    # Issue #342
+    restore_subprocess_executable_issue342(arch)
+
+    print("[build_distrib.py] Successfully built cefpython modules for {arch}"
+          .format(arch=arch))
+
+
+def backup_subprocess_executable_issue342(python):
+    """Use subprocess executable build by Python 2.7 to avoid
+    false-positives by AVs when building subprocess with Python 3.
+    Windows-only issue."""
+    if not WINDOWS:
+        return
+    if python["version2"] == (2, 7):
+        print("[build_distrib.py] Backup subprocess executable built"
+              " with Python 2.7 (Issue #342)")
+        cefpython_binary_basename = get_cefpython_binary_basename(
+                get_os_postfix2_for_arch(python["arch"]))
+        cefpython_binary = os.path.join(BUILD_DIR, cefpython_binary_basename)
+        assert os.path.isdir(cefpython_binary)
+        src = os.path.join(cefpython_binary, "subprocess.exe")
+        dst = os.path.join(BUILD_CEFPYTHON,
+                           "subprocess_py27_{arch}_issue342.exe"
+                           .format(arch=python["arch"]))
+        shutil.copy(src, dst)
+
+
+def restore_subprocess_executable_issue342(arch):
+    """Use subprocess executable build by Python 2.7 to avoid
+    false-positives by AVs when building subprocess with Python 3.
+    Windows-only issue."""
+    if not WINDOWS:
+        return
+    print("[build_distrib.py] Restore subprocess executable built"
+          " with Python 2.7 (Issue #342)")
+    cefpython_binary_basename = get_cefpython_binary_basename(
+            get_os_postfix2_for_arch(arch))
+    cefpython_binary = os.path.join(BUILD_DIR, cefpython_binary_basename)
+    assert os.path.isdir(cefpython_binary)
+    src = os.path.join(BUILD_CEFPYTHON,
+                       "subprocess_py27_{arch}_issue342.exe"
+                       .format(arch=arch))
+    assert os.path.isfile(src)
+    dst = os.path.join(cefpython_binary, "subprocess.exe")
+    shutil.copy(src, dst)
 
 
 def make_packages(python, arch):
-    # Make setup package
+    """Make setup and wheel packages."""
     print("[build_distrib.py] Make setup package for {arch}..."
           .format(arch=arch))
+
+    # Call make_installer.py
     make_installer_py = os.path.join(TOOLS_DIR, "make_installer.py")
     installer_command = ("\"{python}\" {make_installer_py} {version}"
                          .format(python=python["executable"],
diff --git a/tools/run_examples.py b/tools/run_examples.py
index a4a1f0bb..241a9417 100644
--- a/tools/run_examples.py
+++ b/tools/run_examples.py
@@ -36,6 +36,7 @@ def main():
     packages = check_installed_packages()
     examples = list()
     examples.append("hello_world.py")
+    examples.append("tutorial.py")
     succeeded = list()
     failed = list()
     passed = list()