diff --git a/lookup_plugins/bitwarden.py b/lookup_plugins/bitwarden.py
index 2e07b16..c02aac6 100755
--- a/lookup_plugins/bitwarden.py
+++ b/lookup_plugins/bitwarden.py
@@ -69,7 +69,7 @@ class Bitwarden(object):
     def __init__(self, path):
         self._cli_path = path
         try:
-            check_output(self._cli_path)
+            check_output([self._cli_path, "--version"])
         except OSError:
             raise AnsibleError("Command not found: {0}".format(self._cli_path))
 
@@ -82,27 +82,28 @@ class Bitwarden(object):
         return 'BW_SESSION' in os.environ
 
     def _run(self, args):
+        print("%s %s" % (self.cli_path, args))
         p = Popen([self.cli_path] + args, stdin=PIPE, stdout=PIPE, stderr=PIPE)
         out, err = p.communicate()
         rc = p.wait()
         if rc != 0:
             display.debug("Received error when running '{0} {1}': {2}"
                           .format(self.cli_path, args, out))
-            if out.startswith("Vault is locked."):
+            if err.startswith(b"Vault is locked."):
                 raise AnsibleError("Error accessing Bitwarden vault. "
                                    "Run 'bw unlock' to unlock the vault.")
-            elif out.startswith("You are not logged in."):
+            elif err.startswith(b"You are not logged in."):
                 raise AnsibleError("Error accessing Bitwarden vault. "
                                    "Run 'bw login' to login.")
-            elif out.startswith("Failed to decrypt."):
+            elif err.startswith(b"Failed to decrypt."):
                 raise AnsibleError("Error accessing Bitwarden vault. "
                                    "Make sure BW_SESSION is set properly.")
-            elif out.startswith("Not found."):
+            elif err.startswith(b"Not found."):
                 raise AnsibleError("Error accessing Bitwarden vault. "
                                    "Specified item not found.")
             else:
                 raise AnsibleError("Unknown failure in 'bw' command: "
-                                   "{0}".format(out))
+                                   "{0}".format(err))
         return out.strip()
 
     def sync(self):