diff --git a/src/WAConnection/Base.ts b/src/WAConnection/Base.ts
index 1c6a970..e0b1395 100644
--- a/src/WAConnection/Base.ts
+++ b/src/WAConnection/Base.ts
@@ -103,12 +103,13 @@ export default class WAConnectionBase {
             const file = fs.readFileSync(authInfo, { encoding: 'utf-8' }) // load a closed session back if it exists
             authInfo = JSON.parse(file) as AuthenticationCredentialsBrowser
         }
+        const secretBundle: {encKey: string, macKey: string} = typeof authInfo === 'string' ? JSON.parse (authInfo): authInfo
         this.authInfo = {
             clientID: authInfo.WABrowserId.replace(/\"/g, ''),
             serverToken: authInfo.WAToken2.replace(/\"/g, ''),
             clientToken: authInfo.WAToken1.replace(/\"/g, ''),
-            encKey: Buffer.from(authInfo.WASecretBundle.encKey, 'base64'), // decode from base64
-            macKey: Buffer.from(authInfo.WASecretBundle.macKey, 'base64'), // decode from base64
+            encKey: Buffer.from(secretBundle.encKey, 'base64'), // decode from base64
+            macKey: Buffer.from(secretBundle.macKey, 'base64'), // decode from base64
         }
     }
     /**
diff --git a/src/WAConnection/Constants.ts b/src/WAConnection/Constants.ts
index 9dc9f93..8745c86 100644
--- a/src/WAConnection/Constants.ts
+++ b/src/WAConnection/Constants.ts
@@ -27,7 +27,7 @@ export interface AuthenticationCredentialsBase64 {
 }
 export interface AuthenticationCredentialsBrowser {
     WABrowserId: string
-    WASecretBundle: {encKey: string, macKey: string}
+    WASecretBundle: {encKey: string, macKey: string} | string
     WAToken1: string
     WAToken2: string
 }