diff --git a/dist/index.js b/dist/index.js
index 5c4ba6cb..f9b77cdc 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -22,7 +22,7 @@ var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (
 var __importStar = (this && this.__importStar) || function (mod) {
     if (mod && mod.__esModule) return mod;
     var result = {};
-    if (mod != null) for (var k in mod) if (k !== "default" && Object.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
     __setModuleDefault(result, mod);
     return result;
 };
@@ -96,7 +96,9 @@ function downloadRelease(version) {
             downloadPath = yield tc.downloadTool(downloadUrl, undefined, token);
         }
         catch (error) {
-            core.debug(error);
+            if (typeof error === "string" || error instanceof Error) {
+                core.debug(error.toString());
+            }
             throw `Failed to download version ${version}: ${error}`;
         }
         // Extract
@@ -243,7 +245,7 @@ var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (
 var __importStar = (this && this.__importStar) || function (mod) {
     if (mod && mod.__esModule) return mod;
     var result = {};
-    if (mod != null) for (var k in mod) if (k !== "default" && Object.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
     __setModuleDefault(result, mod);
     return result;
 };
@@ -302,13 +304,18 @@ function run() {
             }
             const options = {
                 env: {
-                    ARDUINO_LINT_OFFICIAL: official,
+                    ARDUINO_LINT_OFFICIAL: official, // The official mode is set via an environment variable.
                 },
             };
             yield exec.exec(toolPath, execArgs, options);
         }
         catch (error) {
-            core.setFailed(error.message);
+            if (error instanceof Error) {
+                core.setFailed(error.message);
+            }
+            else {
+                throw error;
+            }
         }
     });
 }
diff --git a/package-lock.json b/package-lock.json
index cd63f0e7..6cc57068 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -11539,9 +11539,9 @@
       }
     },
     "typescript": {
-      "version": "3.9.7",
-      "resolved": "https://registry.npmjs.org/typescript/-/typescript-3.9.7.tgz",
-      "integrity": "sha512-BLbiRkiBzAwsjut4x/dsibSTB6yWpwT5qWmC2OfuCg3GgVQCSgMs4vEctYPhsaGtd0AeuuHMkjZ2h2WG8MSzRw==",
+      "version": "4.5.4",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-4.5.4.tgz",
+      "integrity": "sha512-VgYs2A2QIRuGphtzFV7aQJduJ2gyfTljngLzjpfW9FoYZF6xuw1W0vW9ghCKLfcWrCFxK81CSGRAvS1pn4fIUg==",
       "dev": true
     },
     "union-value": {
diff --git a/package.json b/package.json
index 2bd66898..dd727f18 100644
--- a/package.json
+++ b/package.json
@@ -39,6 +39,6 @@
     "nock": "^10.0.6",
     "prettier": "^2.5.1",
     "ts-jest": "^26.4.4",
-    "typescript": "^3.9.7"
+    "typescript": "^4.5.4"
   }
 }
diff --git a/src/installer.ts b/src/installer.ts
index 5575621a..4d1481d8 100644
--- a/src/installer.ts
+++ b/src/installer.ts
@@ -67,7 +67,9 @@ async function downloadRelease(version: string): Promise<string> {
     const token: string = core.getInput("token", { required: true });
     downloadPath = await tc.downloadTool(downloadUrl, undefined, token);
   } catch (error) {
-    core.debug(error);
+    if (typeof error === "string" || error instanceof Error) {
+      core.debug(error.toString());
+    }
     throw `Failed to download version ${version}: ${error}`;
   }
 
diff --git a/src/main.ts b/src/main.ts
index a3900f2f..cd809914 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -58,7 +58,11 @@ async function run() {
 
     await exec.exec(toolPath, execArgs, options);
   } catch (error) {
-    core.setFailed(error.message);
+    if (error instanceof Error) {
+      core.setFailed(error.message);
+    } else {
+      throw error;
+    }
   }
 }