diff --git a/admin/core/src/main/java/org/apache/karaf/admin/internal/AdminServiceImpl.java b/admin/core/src/main/java/org/apache/karaf/admin/internal/AdminServiceImpl.java
index 93b928a..1725e44 100644
--- a/admin/core/src/main/java/org/apache/karaf/admin/internal/AdminServiceImpl.java
+++ b/admin/core/src/main/java/org/apache/karaf/admin/internal/AdminServiceImpl.java
@@ -396,7 +396,7 @@ public class AdminServiceImpl implements AdminService {
                 String command = "\""
                         + new File(System.getProperty("java.home"), ScriptUtils.isWindows() ? "bin\\java.exe" : "bin/java").getCanonicalPath()
                         + "\" " + opts
-                        + " " + karafOpts
+                        + " " + (karafOpts == null? "" : karafOpts)
                         + " -Djava.util.logging.config.file=\"" + new File(location, "etc/java.util.logging.properties").getCanonicalPath() + "\""
                         + " -Djava.endorsed.dirs=\"" + new File(new File(new File(System.getProperty("java.home"), "jre"), "lib"), "endorsed") + System.getProperty("path.separator") + new File(new File(System.getProperty("java.home"), "lib"), "endorsed") + System.getProperty("path.separator") + new File(libDir, "endorsed").getCanonicalPath() + "\""
                         + " -Djava.ext.dirs=\"" + new File(new File(new File(System.getProperty("java.home"), "jre"), "lib"), "ext") + System.getProperty("path.separator") + new File(new File(System.getProperty("java.home"), "lib"), "ext") + System.getProperty("path.separator") + new File(libDir, "ext").getCanonicalPath() + "\""