diff --git a/homeassistant/components/adguard/config_flow.py b/homeassistant/components/adguard/config_flow.py
index a0ace62386291d527f262a38f41ce84d5cdb9501..c799c4a71355c8ec8ebfefec414608c818c2904c 100644
--- a/homeassistant/components/adguard/config_flow.py
+++ b/homeassistant/components/adguard/config_flow.py
@@ -80,7 +80,7 @@ class AdGuardHomeFlowHandler(ConfigFlow):
         try:
             await adguard.version()
         except AdGuardHomeConnectionError:
-            errors["base"] = "connection_error"
+            errors["base"] = "cannot_connect"
             return await self._show_setup_form(errors)
 
         return self.async_create_entry(
@@ -152,7 +152,7 @@ class AdGuardHomeFlowHandler(ConfigFlow):
         try:
             await adguard.version()
         except AdGuardHomeConnectionError:
-            errors["base"] = "connection_error"
+            errors["base"] = "cannot_connect"
             return await self._show_hassio_form(errors)
 
         return self.async_create_entry(
diff --git a/homeassistant/components/adguard/strings.json b/homeassistant/components/adguard/strings.json
index f010f9e2ade25ac531444b60e90bdc924d01cee2..2658f7344d4efc78403cd1a6f8dce219936b0190 100644
--- a/homeassistant/components/adguard/strings.json
+++ b/homeassistant/components/adguard/strings.json
@@ -17,10 +17,12 @@
         "description": "Do you want to configure Home Assistant to connect to the AdGuard Home provided by the Hass.io add-on: {addon}?"
       }
     },
-    "error": { "connection_error": "Failed to connect." },
+    "error": {
+      "cannot_connect": "[%key:common::config_flow::error::cannot_connect%]"
+    },
     "abort": {
       "existing_instance_updated": "Updated existing configuration.",
-      "single_instance_allowed": "Only a single configuration of AdGuard Home is allowed."
+      "single_instance_allowed": "[%key:common::config_flow::abort::single_instance_allowed%]"
     }
   }
 }
diff --git a/tests/components/adguard/test_config_flow.py b/tests/components/adguard/test_config_flow.py
index e773768ebe66f715cfa9115f1e1e3043861fefbe..36263335dacca711df3fc650f73041d92dfe1315 100644
--- a/tests/components/adguard/test_config_flow.py
+++ b/tests/components/adguard/test_config_flow.py
@@ -53,7 +53,7 @@ async def test_connection_error(hass, aioclient_mock):
 
     assert result["type"] == data_entry_flow.RESULT_TYPE_FORM
     assert result["step_id"] == "user"
-    assert result["errors"] == {"base": "connection_error"}
+    assert result["errors"] == {"base": "cannot_connect"}
 
 
 async def test_full_flow_implementation(hass, aioclient_mock):
@@ -235,4 +235,4 @@ async def test_hassio_connection_error(hass, aioclient_mock):
 
     assert result["type"] == data_entry_flow.RESULT_TYPE_FORM
     assert result["step_id"] == "hassio_confirm"
-    assert result["errors"] == {"base": "connection_error"}
+    assert result["errors"] == {"base": "cannot_connect"}