diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index d2d94db..b72494b 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -3,10 +3,16 @@ Changelog
 
 in development
 --------------
-* Exit hubot on unhandled promise rejections and uncaught exceptions, usually caused by unrecoverable errors (bug fix)
+
+
+0.9.5
+-----
+* Exit hubot on invalid, expired `ST2_API_KEY` / `ST2_AUTH_TOKEN` or any other Unauthorized response from st2 server (bug fix)
+* When st2 username/password is used, re-generate st2 auth token in advance, giving enough time for request to complete, st2client.js (bug fix)
 
 0.9.4
 -----
+* Exit hubot on unhandled promise rejections and uncaught exceptions, usually caused by unrecoverable errors (bug fix)
 * Add pagination support for action aliases - fixes #158 (bug fix)
 
 0.9.3
diff --git a/package.json b/package.json
index 280f7a5..243e00f 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "hubot-stackstorm",
   "description": "A hubot plugin for integrating with StackStorm event-driven infrastructure automation platform.",
-  "version": "0.9.4",
+  "version": "0.9.5",
   "author": "StackStorm, Inc. <info@stackstorm.com>",
   "license": "Apache-2.0",
   "keywords": [
@@ -27,7 +27,7 @@
     "coffee-script": "1.12.7",
     "lodash": "^4.17.11",
     "rsvp": "^4.8.4",
-    "st2client": "^1.1.2",
+    "st2client": "^1.1.3",
     "truncate": "^2.0.1",
     "uuid": "^3.0.0"
   },
diff --git a/scripts/stackstorm.js b/scripts/stackstorm.js
index fe6ff2a..263a8eb 100644
--- a/scripts/stackstorm.js
+++ b/scripts/stackstorm.js
@@ -258,8 +258,10 @@ module.exports = function(robot) {
         robot.logger.info(command_factory.st2_hubot_commands.length + ' commands are loaded');
       })
       .catch(function (err) {
-        var error_msg = 'Failed to retrieve commands from "%s": %s';
-        robot.logger.error(util.format(error_msg, env.ST2_API_URL, err.message));
+        robot.logger.error(util.format('Failed to retrieve commands from "%s": %s', env.ST2_API_URL, err.message));
+        if (err.status === 401 || err.message.includes('Unauthorized')) {
+          throw err;
+        }
       });
   };
 
@@ -397,6 +399,9 @@ module.exports = function(robot) {
       source.onerror = function (err) {
         // TODO: squeeze a little bit more info out of evensource.js
         robot.logger.error('Stream error:', err);
+        if (err.status === 401) {
+          throw err;
+        }
       };
       source.addEventListener('st2.announcement__chatops', function (e) {
         var data;
diff --git a/tests/test-st2-unauthorized.js b/tests/test-st2-unauthorized.js
new file mode 100644
index 0000000..b87c342
--- /dev/null
+++ b/tests/test-st2-unauthorized.js
@@ -0,0 +1,99 @@
+// Copyright 2019 Extreme Networks, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*jshint quotmark:false*/
+/*jshint -W030*/
+/*global describe, it, before, after*/
+'use strict';
+
+var chai = require('chai'),
+  expect = chai.expect,
+  nock = require('nock'),
+  Robot = require('hubot/src/robot');
+
+describe("auth with invalid st2 API key", function() {
+  var stop;
+  var robot = new Robot(null, "mock-adapter", true, "Hubot");
+  var recordedError = null,
+    logs = [],
+    controlledLogger = function(msg) { logs.push(msg); };
+
+  robot.logger.error = controlledLogger;
+  robot.logger.warning = controlledLogger;
+  robot.logger.info = controlledLogger;
+  robot.logger.debug = controlledLogger;
+
+
+  before(function(done) {
+    process.env.ST2_API_KEY = 'aaaa';
+
+    // emulate ST2 API response
+    nock('http://localhost:9101')
+      .get('/v1/actionalias')
+      .query({"limit":"-1","offset":"0"})
+      .reply(401, {"faultstring":"Unauthorized - ApiKey with key_hash=123 not found."});
+
+    // emulate ST2 STREAM response
+    nock('http://localhost:9102')
+      .get('/v1/stream')
+      .query({"st2-api-key":"aaa"})
+      .reply(401, "");
+
+    // hack to detect uncaught exceptions
+    var originalException = process.listeners('uncaughtException').pop();
+    process.removeListener('uncaughtException', originalException);
+    process.prependOnceListener('uncaughtException', function (error) {
+      process.listeners('uncaughtException').push(originalException);
+      recordedError = error;
+      //done();
+    });
+
+    var stackstorm = require("../scripts/stackstorm.js");
+    stackstorm(robot).then(function (result) {
+      stop = result;
+      done();
+    });
+    robot.run();
+  });
+
+  after(function() {
+    stop && stop();
+    robot.server.close();
+    robot.shutdown();
+    // Remove stackstorm.js from the require cache
+    // https://medium.com/@gattermeier/invalidate-node-js-require-cache-c2989af8f8b0
+    delete require.cache[require.resolve("../scripts/stackstorm.js")];
+  });
+
+
+  it("is using ST2_API_KEY as authentication", function () {
+    // debug, if needed
+    //console.log(logs);
+    expect(logs).to.contain('Using ST2_API_KEY as authentication. Expiry will lead to bot exit.');
+  });
+
+  it("fails to retrieve the commands from API", function () {
+    expect(logs).to.include('Failed to retrieve commands from "http://localhost:9101": Unauthorized - ApiKey with key_hash=123 not found.');
+  });
+
+  it("throws an 'Unauthorized' error", function () {
+    expect(JSON.stringify(recordedError)).to.be.equal(
+      '{"name":"APIError","status":401,"message":"Unauthorized - ApiKey with key_hash=123 not found."}'
+    );
+  });
+  
+  it("leads to Hubot shutdown", function () {
+    expect(logs).to.contain('Hubot will shut down ...');
+  });
+});