diff --git a/build.gradle b/build.gradle
index 0dcfb901d..27676381e 100644
--- a/build.gradle
+++ b/build.gradle
@@ -58,7 +58,11 @@ configurations {
 }
 
 tasks.withType(JavaCompile).configureEach {
-  options.compilerArgs << "-Xlint:unchecked" << "-Werror"
+  options.compilerArgs << "-Xlint:unchecked"
+//  Enable the following to highlight all deprecated build errors
+  options.compilerArgs << "-Xlint:deprecation"
+//  Enable the following to stop the build on any warning messages (not just error messages)
+  options.compilerArgs << "-Werror"
 }
 
 // https://github.com/gradle/gradle/issues/16791
diff --git a/src/test/java/uk/gov/hmcts/opal/controllers/advice/GlobalExceptionHandlerTest.java b/src/test/java/uk/gov/hmcts/opal/controllers/advice/GlobalExceptionHandlerTest.java
index 1341d246e..c58ff29da 100644
--- a/src/test/java/uk/gov/hmcts/opal/controllers/advice/GlobalExceptionHandlerTest.java
+++ b/src/test/java/uk/gov/hmcts/opal/controllers/advice/GlobalExceptionHandlerTest.java
@@ -7,6 +7,7 @@
 import org.hibernate.LazyInitializationException;
 import org.hibernate.PropertyValueException;
 import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
 import org.postgresql.util.PSQLException;
 import org.postgresql.util.PSQLState;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -16,6 +17,7 @@
 import org.springframework.dao.DataAccessResourceFailureException;
 import org.springframework.dao.InvalidDataAccessApiUsageException;
 import org.springframework.dao.InvalidDataAccessResourceUsageException;
+import org.springframework.http.HttpInputMessage;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
@@ -307,7 +309,8 @@ void testHandleHttpMediaTypeNotSupportedException() {
 
     @Test
     void testHandleHttpMessageNotReadableException() {
-        HttpMessageNotReadableException exception = new HttpMessageNotReadableException("Cannot read message");
+        HttpInputMessage msg = Mockito.mock(HttpInputMessage.class);
+        HttpMessageNotReadableException exception = new HttpMessageNotReadableException("Cannot read message", msg);
         ResponseEntity<Map<String, String>> response = globalExceptionHandler
             .handleHttpMessageNotReadableException(exception);
 
diff --git a/src/test/java/uk/gov/hmcts/opal/scheduler/job/FileHandlerJobTest.java b/src/test/java/uk/gov/hmcts/opal/scheduler/job/FileHandlerJobTest.java
index 7f2b2880f..58bb9ad2a 100644
--- a/src/test/java/uk/gov/hmcts/opal/scheduler/job/FileHandlerJobTest.java
+++ b/src/test/java/uk/gov/hmcts/opal/scheduler/job/FileHandlerJobTest.java
@@ -40,7 +40,7 @@ class FileHandlerJobTest {
 
     @BeforeEach
     void setUp() {
-        MockitoAnnotations.initMocks(this);
+        MockitoAnnotations.openMocks(this);
     }
 
     @Test
diff --git a/src/test/java/uk/gov/hmcts/opal/scheduler/job/LogRetentionJobTest.java b/src/test/java/uk/gov/hmcts/opal/scheduler/job/LogRetentionJobTest.java
index 20300a382..9f780acf4 100644
--- a/src/test/java/uk/gov/hmcts/opal/scheduler/job/LogRetentionJobTest.java
+++ b/src/test/java/uk/gov/hmcts/opal/scheduler/job/LogRetentionJobTest.java
@@ -36,7 +36,7 @@ class LogRetentionJobTest {
 
     @BeforeEach
     void setUp() {
-        MockitoAnnotations.initMocks(this);
+        MockitoAnnotations.openMocks(this);
     }
 
     @Test
diff --git a/src/test/java/uk/gov/hmcts/opal/scheduler/service/JobServiceTest.java b/src/test/java/uk/gov/hmcts/opal/scheduler/service/JobServiceTest.java
index 5163813d2..c73e06285 100644
--- a/src/test/java/uk/gov/hmcts/opal/scheduler/service/JobServiceTest.java
+++ b/src/test/java/uk/gov/hmcts/opal/scheduler/service/JobServiceTest.java
@@ -44,7 +44,7 @@ class JobServiceTest {
 
     @BeforeEach
     void setUp() {
-        MockitoAnnotations.initMocks(this);
+        MockitoAnnotations.openMocks(this);
     }
 
     @Test
diff --git a/src/test/java/uk/gov/hmcts/opal/scheduler/service/LogRetentionServiceTest.java b/src/test/java/uk/gov/hmcts/opal/scheduler/service/LogRetentionServiceTest.java
index b7335e099..711e1eb2d 100644
--- a/src/test/java/uk/gov/hmcts/opal/scheduler/service/LogRetentionServiceTest.java
+++ b/src/test/java/uk/gov/hmcts/opal/scheduler/service/LogRetentionServiceTest.java
@@ -19,7 +19,7 @@ class LogRetentionServiceTest {
 
     @BeforeEach
     void setUp() {
-        MockitoAnnotations.initMocks(this);
+        MockitoAnnotations.openMocks(this);
         logRetentionService = new LogRetentionService(jdbcTemplate);
     }
 
@@ -39,4 +39,3 @@ void testDeleteExpiredLogAudit_DatabaseError() {
         verify(jdbcTemplate).execute("CALL delete_expired_log_audit()");
     }
 }
-