diff --git a/platform/platform-impl/src/com/intellij/ide/impl/ProjectUtil.java b/platform/platform-impl/src/com/intellij/ide/impl/ProjectUtil.java
index 65eaa3611e1a..b6c12c93579c 100644
--- a/platform/platform-impl/src/com/intellij/ide/impl/ProjectUtil.java
+++ b/platform/platform-impl/src/com/intellij/ide/impl/ProjectUtil.java
@@ -33,6 +33,7 @@ import com.intellij.openapi.ui.Messages;
 import com.intellij.openapi.util.ActionCallback;
 import com.intellij.openapi.util.InvalidDataException;
 import com.intellij.openapi.util.io.FileUtil;
+import com.intellij.openapi.util.io.FileUtilRt;
 import com.intellij.openapi.vfs.LocalFileSystem;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.openapi.wm.*;
@@ -298,10 +299,11 @@ public class ProjectUtil {
 
     File parent = projectFile.getParentFile();
     if (parent.getName().equals(Project.DIRECTORY_STORE_FOLDER)) {
-      projectFile = parent;
       parent = parent.getParentFile();
+      return parent != null && FileUtil.pathsEqual(parent.getPath(), existingBaseDirPath);
     }
-    return parent != null && FileUtil.pathsEqual(parent.getPath(), existingBaseDirPath) && projectFile.getName().equals(Project.DIRECTORY_STORE_FOLDER);
+    return FileUtil.pathsEqual(parent.getPath(), existingBaseDirPath) &&
+           ProjectFileType.DEFAULT_EXTENSION.equals(FileUtilRt.getExtension(projectFile.getName()));
   }
 
   public static void focusProjectWindow(final Project p, boolean executeIfAppInactive) {
diff --git a/platform/platform-tests/testSrc/com/intellij/openapi/project/impl/ProjectOpeningTest.java b/platform/platform-tests/testSrc/com/intellij/openapi/project/impl/ProjectOpeningTest.java
index 90aa6bc185dc..ef2f7879665b 100644
--- a/platform/platform-tests/testSrc/com/intellij/openapi/project/impl/ProjectOpeningTest.java
+++ b/platform/platform-tests/testSrc/com/intellij/openapi/project/impl/ProjectOpeningTest.java
@@ -93,9 +93,11 @@ public class ProjectOpeningTest extends PlatformTestCase {
     assertTrue(ProjectUtil.isSameProject(projectDir.getAbsolutePath(), dirBasedProject));
     assertFalse(ProjectUtil.isSameProject(createTempDir("project2").getAbsolutePath(), dirBasedProject));
     File iprFilePath = new File(projectDir, "project.ipr");
-    assertFalse(ProjectUtil.isSameProject(iprFilePath.getAbsolutePath(), dirBasedProject));
+    assertTrue(ProjectUtil.isSameProject(iprFilePath.getAbsolutePath(), dirBasedProject));
     File miscXmlFilePath = new File(projectDir, ".idea/misc.xml");
     assertTrue(ProjectUtil.isSameProject(miscXmlFilePath.getAbsolutePath(), dirBasedProject));
+    File someOtherFilePath = new File(projectDir, "misc.xml");
+    assertFalse(ProjectUtil.isSameProject(someOtherFilePath.getAbsolutePath(), dirBasedProject));
   }
 
   public void testIsSameProjectForFileBasedProject() throws IOException {