diff --git a/ui/code-owners-api.js b/ui/code-owners-api.js
index 408428b..a1a1aed 100644
--- a/ui/code-owners-api.js
+++ b/ui/code-owners-api.js
@@ -15,12 +15,10 @@
  * limitations under the License.
  */
 
-
 // TODO: Try to remove it. The ResponseError and getErrorMessage duplicates
 // code from the gr-plugin-rest-api.ts. This code is required because
 // we want custom error processing in some functions. For details see
 // the original gr-plugin-rest-api.ts file/
-
 class ResponseError extends Error {
   constructor(response) {
     super();
@@ -28,6 +26,12 @@
   }
 }
 
+export class ServerConfigurationError extends Error {
+  constructor(msg) {
+    super(msg);
+  }
+}
+
 async function getErrorMessage(response) {
   const text = await response.text();
   return text ?
@@ -46,13 +50,39 @@
   }
 
   /**
+   * Send a get request and provides custom response-code handling
+   */
+  async _get(url) {
+    const errFn = (response, error) => {
+      if (error) throw error;
+      if (response) throw new ResponseError(response);
+      throw new Error('Generic REST API error');
+    };
+    try {
+      return await this.restApi.send(
+          'GET',
+          url,
+          undefined,
+          errFn
+      );
+    } catch (err) {
+      if (err instanceof ResponseError && err.response.status === 409) {
+        return getErrorMessage(err.response).then(msg => {
+          throw new ServerConfigurationError(msg);
+        });
+      }
+      throw err;
+    }
+  }
+
+  /**
    * Returns a promise fetching the owner statuses for all files within the change.
    *
    * @doc https://gerrit.googlesource.com/plugins/code-owners/+/refs/heads/master/resources/Documentation/rest-api.md#change-endpoints
    * @param {string} changeId
    */
   listOwnerStatus(changeId) {
-    return this.restApi.get(`/changes/${changeId}/code_owners.status`);
+    return this._get(`/changes/${changeId}/code_owners.status`);
   }
 
   /**
@@ -63,7 +93,7 @@
    * @param {string} path
    */
   listOwnersForPath(changeId, path, limit) {
-    return this.restApi.get(
+    return this._get(
         `/changes/${changeId}/revisions/current/code_owners` +
         `/${encodeURIComponent(path)}?limit=${limit}&o=DETAILS`
     );
@@ -78,7 +108,7 @@
    * @param {string} path
    */
   getConfigForPath(project, branch, path) {
-    return this.restApi.get(
+    return this._get(
         `/projects/${encodeURIComponent(project)}/` +
         `branches/${encodeURIComponent(branch)}/` +
         `code_owners.config/${encodeURIComponent(path)}`
@@ -93,19 +123,11 @@
    * @param {string} branch
    */
   async getBranchConfig(project, branch) {
-    const errFn = (response, error) => {
-      if (error) throw error;
-      if (response) throw new ResponseError(response);
-      throw new Error('Generic REST API error');
-    }
     try {
-      const config = await this.restApi.send(
-          'GET',
+      const config = await this._get(
           `/projects/${encodeURIComponent(project)}/` +
           `branches/${encodeURIComponent(branch)}/` +
-          `code_owners.branch_config`,
-          undefined,
-          errFn
+          `code_owners.branch_config`
       );
       if (config.override_approval && !(config.override_approval
           instanceof Array)) {
@@ -116,7 +138,7 @@
         return {...config, override_approval: [config.override_approval]};
       }
       return config;
-    } catch(err) {
+    } catch (err) {
       if (err instanceof ResponseError) {
         if (err.response.status === 404) {
           // The 404 error means that the branch doesn't exist and
diff --git a/ui/code-owners-banner.js b/ui/code-owners-banner.js
index 4e4b07e..1aa9e58 100644
--- a/ui/code-owners-banner.js
+++ b/ui/code-owners-banner.js
@@ -15,7 +15,7 @@
  * limitations under the License.
  */
 import {CodeOwnersModelMixin} from './code-owners-model-mixin.js';
-import {PluginState} from './code-owners-model.js';
+import {PluginState, isPluginErrorState} from './code-owners-model.js';
 
 // There are 2 elements in this file:
 // CodeOwnersBanner - visual elements. This element is shown at the top
@@ -79,7 +79,7 @@
           margin-left: var(--spacing-l);
         }
       </style>
-      <span class="text">Error: Code-owners plugin has failed</span>
+      <span class="text">[[_getErrorText(pluginStatus)]]</span>
       <gr-button link on-click="_showFailDetails">
         Details
       </gr-button>
@@ -112,7 +112,14 @@
   }
 
   _computeHidden(pluginStatus) {
-    return !pluginStatus || pluginStatus.state !== PluginState.Failed;
+    return !pluginStatus || !isPluginErrorState(pluginStatus.state);
+  }
+
+  _getErrorText(pluginStatus) {
+    return !pluginStatus || pluginStatus.state === PluginState.Failed ?
+      'Error: Code-owners plugin has failed' :
+      'The code-owners plugin has configuration issue. ' +
+      'Please contact the project owner or the host admin.';
   }
 
   _showFailDetails() {
@@ -189,7 +196,7 @@
         branchState: 'LOADING',
       };
     }
-    if (pluginStatus.state === PluginState.Failed) {
+    if (isPluginErrorState(pluginStatus.state)) {
       return {
         change,
         branchState: 'FAILED',
diff --git a/ui/code-owners-model-loader.js b/ui/code-owners-model-loader.js
index 2fa18ac..cdc04dd 100644
--- a/ui/code-owners-model-loader.js
+++ b/ui/code-owners-model-loader.js
@@ -16,6 +16,7 @@
  */
 
 import {SuggestionsState} from './code-owners-model.js';
+import {ServerConfigurationError} from './code-owners-api.js';
 
 /**
  * ModelLoader provides a method for loading data into the model.
@@ -39,6 +40,10 @@
     try {
       newValue = await propertyLoader();
     } catch (e) {
+      if (e instanceof ServerConfigurationError) {
+        this.ownersModel.setServerConfigurationError(e.message);
+        return;
+      }
       console.error(e);
       this.ownersModel.setPluginFailed(e.message);
       return;
diff --git a/ui/code-owners-model.js b/ui/code-owners-model.js
index 079eb86..ad536b4 100644
--- a/ui/code-owners-model.js
+++ b/ui/code-owners-model.js
@@ -25,9 +25,15 @@
 export const PluginState = {
   Enabled: 'Enabled',
   Disabled: 'Disabled',
+  ServerConfigurationError: 'ServerConfigurationError',
   Failed: 'Failed',
 };
 
+export function isPluginErrorState(state) {
+  return state === PluginState.ServerConfigurationError ||
+      state === PluginState.Failed;
+}
+
 export const SuggestionsType = {
   BEST_SUGGESTIONS: 'BEST_SUGGESTIONS',
   ALL_SUGGESTIONS: 'ALL_SUGGESTIONS',
@@ -148,6 +154,11 @@
       PluginState.Enabled : PluginState.Disabled});
   }
 
+  setServerConfigurationError(failedMessage) {
+    this._setPluginStatus({state: PluginState.ServerConfigurationError,
+      failedMessage});
+  }
+
   setPluginFailed(failedMessage) {
     this._setPluginStatus({state: PluginState.Failed, failedMessage});
   }
@@ -163,7 +174,7 @@
       return status1 === status2;
     }
     if (status1.state !== status2.state) return false;
-    return status1.state === PluginState.Failed ?
+    return isPluginErrorState(status1.state)?
       status1.failedMessage === status2.failedMessage :
       true;
   }
diff --git a/ui/owner-requirement.js b/ui/owner-requirement.js
index a173c75..e6ced63 100644
--- a/ui/owner-requirement.js
+++ b/ui/owner-requirement.js
@@ -18,7 +18,7 @@
 import {OwnerStatus} from './code-owners-fetcher.js';
 import {CodeOwnersModelMixin} from './code-owners-model-mixin.js';
 import {showPluginFailedMessage} from './code-owners-banner.js';
-import {PluginState} from './code-owners-model.js';
+import {isPluginErrorState} from './code-owners-model.js';
 
 /**
  * Owner requirement control for `submit-requirement-item-code-owners` endpoint.
@@ -137,7 +137,7 @@
   }
 
   _pluginFailed(pluginStatus) {
-    return pluginStatus && pluginStatus.state === PluginState.Failed;
+    return pluginStatus && isPluginErrorState(pluginStatus.state);
   }
 
   _onStatusChanged(status, userRole) {