diff --git a/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/actions/CCCreateCourseArchive.java b/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/actions/CCCreateCourseArchive.java
index 23cfece28509..9b672765ec7d 100644
--- a/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/actions/CCCreateCourseArchive.java
+++ b/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/actions/CCCreateCourseArchive.java
@@ -115,7 +115,7 @@ public class CCCreateCourseArchive extends DumbAwareAction {
           public boolean accept(File pathname) {
             String name = pathname.getName();
             String nameWithoutExtension = FileUtil.getNameWithoutExtension(pathname);
-            if (nameWithoutExtension.endsWith(".answer") || name.contains("_windows") || name.contains(".idea")
+            if (nameWithoutExtension.endsWith(".answer") || name.contains(EduNames.WINDOWS_POSTFIX) || name.contains(".idea")
               || FileUtil.filesEqual(pathname, zipFile)) {
               return false;
             }
diff --git a/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/actions/CCRunTestsAction.java b/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/actions/CCRunTestsAction.java
index f1d9d6cba063..aa065bf35451 100644
--- a/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/actions/CCRunTestsAction.java
+++ b/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/actions/CCRunTestsAction.java
@@ -201,7 +201,7 @@ public abstract class CCRunTestsAction extends AnAction {
       }
       VirtualFile[] taskDirChildren = taskDir.getChildren();
       for (VirtualFile file : taskDirChildren) {
-        if (file.getName().contains("_windows")) {
+        if (file.getName().contains(EduNames.WINDOWS_POSTFIX)) {
           file.delete(project);
         }
         if (CCProjectService.getInstance(project).isTaskFile(file)) {
diff --git a/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/projectView/CCTreeStructureProvider.java b/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/projectView/CCTreeStructureProvider.java
index e3a0ae7a3127..d6e4c5347b62 100644
--- a/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/projectView/CCTreeStructureProvider.java
+++ b/python/educational/course-creator/src/com/jetbrains/edu/coursecreator/projectView/CCTreeStructureProvider.java
@@ -8,6 +8,7 @@ import com.intellij.openapi.project.DumbAware;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.psi.PsiDirectory;
+import com.jetbrains.edu.EduNames;
 import com.jetbrains.edu.coursecreator.CCProjectService;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -40,7 +41,7 @@ public class CCTreeStructureProvider implements TreeStructureProvider, DumbAware
             continue;
           }
           if (CCProjectService.getInstance(project).isTaskFile(virtualFile)
-              || virtualFile.getName().contains("_windows")) {
+              || virtualFile.getName().contains(EduNames.WINDOWS_POSTFIX)) {
             continue;
           }
         }
diff --git a/python/educational/interactive-learning/src/com/jetbrains/edu/learning/actions/StudyCheckAction.java b/python/educational/interactive-learning/src/com/jetbrains/edu/learning/actions/StudyCheckAction.java
index 920709b9d119..a47b5a13cbbf 100644
--- a/python/educational/interactive-learning/src/com/jetbrains/edu/learning/actions/StudyCheckAction.java
+++ b/python/educational/interactive-learning/src/com/jetbrains/edu/learning/actions/StudyCheckAction.java
@@ -35,6 +35,7 @@ import com.intellij.openapi.wm.WindowManager;
 import com.intellij.openapi.wm.ex.StatusBarEx;
 import com.intellij.openapi.wm.ex.WindowManagerEx;
 import com.jetbrains.edu.EduDocumentListener;
+import com.jetbrains.edu.EduNames;
 import com.jetbrains.edu.EduUtils;
 import com.jetbrains.edu.courseFormat.AnswerPlaceholder;
 import com.jetbrains.edu.courseFormat.Task;
@@ -91,7 +92,7 @@ public class StudyCheckAction extends DumbAwareAction {
       if (virtualFile == null) {
         continue;
       }
-      String windowsFileName = virtualFile.getNameWithoutExtension() + "_windows";
+      String windowsFileName = virtualFile.getNameWithoutExtension() + EduNames.WINDOWS_POSTFIX;
       final VirtualFile windowsFile = taskDir.findChild(windowsFileName);
       if (windowsFile != null) {
         ApplicationManager.getApplication().runWriteAction(new Runnable() {
diff --git a/python/educational/src/com/jetbrains/edu/EduNames.java b/python/educational/src/com/jetbrains/edu/EduNames.java
index 697ef41190ce..12ced622e4ac 100644
--- a/python/educational/src/com/jetbrains/edu/EduNames.java
+++ b/python/educational/src/com/jetbrains/edu/EduNames.java
@@ -26,6 +26,7 @@ public class EduNames {
   public static final String USER_TEST_INPUT = "input";
   public static final String USER_TEST_OUTPUT = "output";
   public static final String WINDOW_POSTFIX = "_window.";
+  public static final String WINDOWS_POSTFIX = "_windows";
   public static final String TASK = "task";
   public static final String USER_TESTS = "userTests";
   public static final String TESTS_FILE = "tests.py";
diff --git a/python/educational/src/com/jetbrains/edu/EduUtils.java b/python/educational/src/com/jetbrains/edu/EduUtils.java
index f80c843b2722..c72b8fb388bb 100644
--- a/python/educational/src/com/jetbrains/edu/EduUtils.java
+++ b/python/educational/src/com/jetbrains/edu/EduUtils.java
@@ -105,7 +105,7 @@ public class EduUtils {
       return null;
     }
     if (taskDir != null) {
-      final String name = file.getNameWithoutExtension() + "_windows";
+      final String name = file.getNameWithoutExtension() + EduNames.WINDOWS_POSTFIX;
       PrintWriter printWriter = null;
       try {
         fileWindows = taskDir.createChildData(taskFile, name);