diff --git a/instances/tests/test_root_pass.py b/instances/tests/test_root_pass.py
index 05b01197..0c889faf 100644
--- a/instances/tests/test_root_pass.py
+++ b/instances/tests/test_root_pass.py
@@ -169,6 +169,24 @@ class GuestAgentAccessTestCase(TestCase):
         self.assertEqual(self.post("rootpasswd", {"passwd": "S3cret-pass"}),
                          ["guest agent command failed: user root not found"])
 
+    def test_a_command_that_timed_out_may_still_be_made(self):
+        # sent to the agent: it runs when the agent answers again; a failed
+        # synchronization sends nothing
+        from libvirt import VIR_ERR_AGENT_UNRESPONSIVE
+
+        for code, text, note in (
+            (112, "guest agent command timed out", True),  # VIR_ERR_AGENT_COMMAND_TIMEOUT
+            (VIR_ERR_AGENT_UNRESPONSIVE, "Guest agent is not responding", False),
+        ):
+            with self.subTest(code=code):
+                err = libvirtError(text)
+                err.get_error_code = lambda code=code: code
+                self.proxy.set_user_password.side_effect = err
+                self.proxy.add_authorized_key.side_effect = err
+                expected = text + (" The change may still be made when the agent answers again." if note else "")
+                self.assertEqual(self.post("rootpasswd", {"passwd": "S3cret-pass"})[-1], expected)
+                self.assertEqual(self.post("add_public_key", {"sshkeyid": self.key.id})[-1], expected)
+
     def test_a_user_who_does_not_see_hosts_gets_no_connection_details(self):
         from accounts.models import UserInstance
         from django.contrib.auth import get_user_model
diff --git a/instances/views.py b/instances/views.py
index 89cec857..9cd5e7af 100755
--- a/instances/views.py
+++ b/instances/views.py
@@ -869,6 +869,20 @@ def gstfsd_request(hostname, data):
 AGENT_OR_SHUT_OFF = _("Shut the VM down, or start its QEMU guest agent, and try again")
 
 
+# libvirt's value; bindings built against older libvirt (Ubuntu 24.04's) lack
+# the name, and the code comes from the host's libvirtd
+VIR_ERR_AGENT_COMMAND_TIMEOUT = 112
+
+
+def access_error(request, err):
+    """The error of a root password or SSH key change. A command that timed
+    out was sent to the agent, which still runs it when it answers again."""
+    text = error_text(request, err)
+    if isinstance(err, libvirtError) and err.get_error_code() == VIR_ERR_AGENT_COMMAND_TIMEOUT:
+        text += " " + _("The change may still be made when the agent answers again.")
+    return text
+
+
 @require_POST
 @serialize_instance_mutation
 def set_root_pass(request, pk):
@@ -890,7 +904,7 @@ def set_root_pass(request, pk):
                         else:
                             instance.proxy.set_user_password("root", passwd_hash)
                 except (util.OperationError, libvirtError) as err:
-                    messages.error(request, error_text(request, err))
+                    messages.error(request, access_error(request, err))
                 else:
                     messages.success(request, _("Reset root password"))
             else:
@@ -928,7 +942,7 @@ def add_public_key(request, pk):
                     else:
                         instance.proxy.add_authorized_key("root", publickey.keypublic)
             except (util.OperationError, libvirtError) as err:
-                messages.error(request, error_text(request, err))
+                messages.error(request, access_error(request, err))
             else:
                 messages.success(request, _("Installed new SSH public key %(keyname)s") % {
                     "keyname": publickey.keyname