diff --git a/zeppelin-server/src/main/java/org/apache/zeppelin/conf/ZeppelinConfiguration.java b/zeppelin-server/src/main/java/org/apache/zeppelin/conf/ZeppelinConfiguration.java
index 252fd51a9bd..179dcce6e85 100644
--- a/zeppelin-server/src/main/java/org/apache/zeppelin/conf/ZeppelinConfiguration.java
+++ b/zeppelin-server/src/main/java/org/apache/zeppelin/conf/ZeppelinConfiguration.java
@@ -353,7 +353,7 @@ public String getServerContextPath() {
 
   public String getKeyStorePath() {
     String path = getString(ConfVars.ZEPPELIN_SSL_KEYSTORE_PATH);
-    if (path != null && path.startsWith("/") || isWindowsPath(path)) {
+    if (path != null && (path.startsWith("/") || isWindowsPath(path))) {
       return path;
     } else {
       return getAbsoluteDir(
@@ -385,7 +385,7 @@ public String getTrustStorePath() {
     if (path == null) {
       path = getKeyStorePath();
     }
-    if (path != null && path.startsWith("/") || isWindowsPath(path)) {
+    if (path != null && (path.startsWith("/") || isWindowsPath(path))) {
       return path;
     } else {
       return getAbsoluteDir(
@@ -667,7 +667,7 @@ public String getInterpreterPortRange() {
   }
 
   public boolean isWindowsPath(String path){
-    return path.matches("^[A-Za-z]:\\\\.*");
+    return path != null && path.matches("^[A-Za-z]:\\\\.*");
   }
 
   public boolean isPathWithScheme(String path){
diff --git a/zeppelin-server/src/test/java/org/apache/zeppelin/conf/ZeppelinConfigurationTest.java b/zeppelin-server/src/test/java/org/apache/zeppelin/conf/ZeppelinConfigurationTest.java
index 63fcd0da212..a5cb0037fd0 100644
--- a/zeppelin-server/src/test/java/org/apache/zeppelin/conf/ZeppelinConfigurationTest.java
+++ b/zeppelin-server/src/test/java/org/apache/zeppelin/conf/ZeppelinConfigurationTest.java
@@ -72,6 +72,14 @@ void isWindowsPathTestFalse() {
     assertFalse(isIt);
   }
 
+  @Test
+  void isWindowsPathTestNull() {
+
+    ZeppelinConfiguration zConf = ZeppelinConfiguration.load("zeppelin-test-site.xml");
+    Boolean isIt = zConf.isWindowsPath(null);
+    assertFalse(isIt);
+  }
+
   @Test
   void isPathWithSchemeTestTrue() {