diff --git a/poi-ooxml/src/test/java/org/apache/poi/xssf/streaming/TestSXSSFUnicodeSurrogates.java b/poi-ooxml/src/test/java/org/apache/poi/xssf/streaming/TestSXSSFUnicodeSurrogates.java
index aba3a2f3768..360bd0576df 100644
--- a/poi-ooxml/src/test/java/org/apache/poi/xssf/streaming/TestSXSSFUnicodeSurrogates.java
+++ b/poi-ooxml/src/test/java/org/apache/poi/xssf/streaming/TestSXSSFUnicodeSurrogates.java
@@ -18,6 +18,7 @@ Licensed to the Apache Software Foundation (ASF) under one or more
 package org.apache.poi.xssf.streaming;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import org.apache.poi.ss.usermodel.Cell;
 import org.apache.poi.ss.usermodel.Row;
@@ -62,7 +63,7 @@ void testWriteUnicodeSurrogates() throws IOException {
                 assertEquals(unicodeText, cell2.getStringCellValue());
             }
         } finally {
-            tf.delete();
+            assertTrue(tf.delete());
         }
     }
 }
diff --git a/poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFUnicodeSurrogates.java b/poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFUnicodeSurrogates.java
index 506e0dead8b..48c116eb157 100644
--- a/poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFUnicodeSurrogates.java
+++ b/poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFUnicodeSurrogates.java
@@ -18,6 +18,7 @@ Licensed to the Apache Software Foundation (ASF) under one or more
 package org.apache.poi.xssf.usermodel;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import org.apache.poi.ss.usermodel.Cell;
 import org.apache.poi.ss.usermodel.Row;
@@ -61,7 +62,7 @@ void testWriteUnicodeSurrogates() throws IOException {
                 assertEquals(unicodeText, cell2.getStringCellValue());
             }
         } finally {
-            tf.delete();
+            assertTrue(tf.delete());
         }
     }
 }
diff --git a/poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFWorkbook.java b/poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFWorkbook.java
index 8d258bb2898..9e1a7cc0f34 100644
--- a/poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFWorkbook.java
+++ b/poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFWorkbook.java
@@ -1479,7 +1479,7 @@ void readFromZipStream() throws IOException {
             }
             assertEquals(2, count);
         } finally {
-            tempFile.delete();
+            assertTrue(tempFile.delete());
         }
     }
 
diff --git a/poi/src/test/java/org/apache/poi/hssf/usermodel/TestPOIFSProperties.java b/poi/src/test/java/org/apache/poi/hssf/usermodel/TestPOIFSProperties.java
index 4faf1647314..e9a6fbf43eb 100644
--- a/poi/src/test/java/org/apache/poi/hssf/usermodel/TestPOIFSProperties.java
+++ b/poi/src/test/java/org/apache/poi/hssf/usermodel/TestPOIFSProperties.java
@@ -19,6 +19,7 @@ Licensed to the Apache Software Foundation (ASF) under one or more
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
@@ -89,7 +90,7 @@ private void setTitle(POIFSFileSystem fs) throws NoPropertySetStreamException, I
 
         summary1.setTitle(title);
         //write the modified property back to POIFS
-        fs.getRoot().getEntryCaseInsensitive(SummaryInformation.DEFAULT_STREAM_NAME).delete();
+        assertTrue(fs.getRoot().getEntryCaseInsensitive(SummaryInformation.DEFAULT_STREAM_NAME).delete());
         fs.createDocument(summary1.toInputStream(), SummaryInformation.DEFAULT_STREAM_NAME);
 
         // check that the information was added successfully to the filesystem object
diff --git a/poi/src/test/java/org/apache/poi/poifs/filesystem/TestPOIFSStream.java b/poi/src/test/java/org/apache/poi/poifs/filesystem/TestPOIFSStream.java
index 7f25ca751da..0b97d8eb8c7 100644
--- a/poi/src/test/java/org/apache/poi/poifs/filesystem/TestPOIFSStream.java
+++ b/poi/src/test/java/org/apache/poi/poifs/filesystem/TestPOIFSStream.java
@@ -1817,7 +1817,7 @@ void readWriteRead(String file, Function<String,POIFSFileSystem> opener) throws
                         main4096[4095] = -11;
                         testDir.createDocument("Normal4096", new ByteArrayInputStream(main4096));
 
-                        root.getEntryCaseInsensitive("Tags").delete();
+                        assertTrue(root.getEntryCaseInsensitive("Tags").delete());
 
 
                         // Write out, re-load
@@ -1848,7 +1848,7 @@ void readWriteRead(String file, Function<String,POIFSFileSystem> opener) throws
 
 
                             // Delete a directory, and add one more
-                            testDir.getEntryCaseInsensitive("Testing 456").delete();
+                            assertTrue(testDir.getEntryCaseInsensitive("Testing 456").delete());
                             testDir.createDirectory("Testing ABC");
 
 
@@ -1903,7 +1903,7 @@ void readWriteRead(String file, Function<String,POIFSFileSystem> opener) throws
 
 
                                     // Delete a mini stream, add one more
-                                    testDir.getEntryCaseInsensitive("Mini").delete();
+                                    assertTrue(testDir.getEntryCaseInsensitive("Mini").delete());
 
                                     byte[] mini3 = new byte[]{42, 0, 42, 0, 42, 0, 42};
                                     testDir.createDocument("Mini3", new ByteArrayInputStream(mini3));
@@ -2179,8 +2179,8 @@ void createWriteRead() throws IOException {
 
 
                 // Delete a couple of streams
-                miniDoc.delete();
-                normDoc.delete();
+                assertTrue(miniDoc.delete());
+                assertTrue(normDoc.delete());
 
 
                 // Check - will have un-used sectors now