1 files changed, 6 insertions, 2 deletions
diff --git a/src/org/traccar/BaseProtocol.java b/src/org/traccar/BaseProtocol.java
index 62ee99946..4e5df329c 100644
--- a/src/org/traccar/BaseProtocol.java
+++ b/src/org/traccar/BaseProtocol.java
@@ -95,8 +95,12 @@ public abstract class BaseProtocol implements Protocol {
             if (command.getType().equals(Command.TYPE_CUSTOM)) {
                 Context.getSmsManager().sendMessageSync(destAddress, command.getString(Command.KEY_DATA), true);
             } else if (supportedTextCommands.contains(command.getType()) && textCommandEncoder != null) {
-                Context.getSmsManager().sendMessageSync(destAddress,
-                        (String) textCommandEncoder.encodeCommand(command), true);
+                String encodedCommand = (String) textCommandEncoder.encodeCommand(command);
+                if (encodedCommand != null) {
+                    Context.getSmsManager().sendMessageSync(destAddress, encodedCommand, true);
+                } else {
+                    throw new RuntimeException("Failed to encode command");
+                }
             } else {
                 throw new RuntimeException(
                         "Command " + command.getType() + " is not supported in protocol " + getName());