---
title: "Errors"
url: https://docs.catalyst.zoho.com/en/sdk/ios/v2/errors/
description: "This help page lists the common errors that can occur in your Catalyst iOS app executions"
last_updated: 2023-09-02T19:36:41Z
service: All Services
type: general
related_links:
  - name: "Developer Tools"
    url: /en/getting-started/set-up-a-catalyst-project/developer-tools
---

# Errors

Errors are the unexpected faulty behaviours that occur during the app execution. All errors and exceptions in Catalyst iOS apps are handled by enumerations called `ZCatalystError`, defined in the iOS SDK package.

If an error occurs in your app, the following properties of the error are returned:

* `code`: Unique identifier of the error
* `message`: General description about the error
* `details`: Additional information about the error

A list of common error codes thrown by the Catalyst iOS SDK and their descriptions are given below:

<table class="content-table">
<thead>
<tr>
<th class="w30p">Error Codes</th>
<th class="w70p">Descriptions</th>
</tr>
</thead>
<tbody>
<tr>
<td><strong>INVALID_DATA</strong></td>
<td>Data is in an invalid format</td>
</tr>
<tr>
<td><strong>INTERNAL_ERROR</strong></td>
<td>Error occurred due to internal problems, servers, or something else</td>
</tr>
<tr>
<td><strong>RESPONSE_NIL</strong></td>
<td>No response was returned from the server</td>
</tr>
<tr>
<td><strong>TOKEN_FETCH_ERROR</strong></td>
<td>Failed to fetch the access token</td>
</tr>
<tr>
<td><strong>OAUTH_FETCH_ERROR</strong></td>
<td>Error occurred while fetching the OAUTH token</td>
</tr>
<tr>
<td><strong>UNABLE_TO_CONSTRUCT_URL</strong></td>
<td>Error occurred while constructing the URL</td>
</tr>
<tr>
<td><strong>PROCESSING_ERROR</strong></td>
<td>Error occurred while processing the data</td>
</tr>
<tr>
<td><strong>TYPECAST_ERROR</strong></td>
<td>Error occurred while type-casting the data</td>
</tr>
<tr>
<td><strong>NO_INTERNET_CONNECTION</strong></td>
<td>Device is not connected to the internet</td>
</tr>
<tr>
<td><strong>REQUEST_TIMEOUT</strong></td>
<td>Response from the server did not arrive on time</td>
</tr>
<tr>
<td><strong>NETWORK_CONNECTION_LOST</strong></td>
<td>Device has lost its connection with the Internet</td>
</tr>
<tr>
<td><strong>INITIALIZATION_ERROR</strong></td>
<td>Error occurred while initializing the SDK</td>
</tr>
<tr>
<td><strong>FUNCTION_EXECUTION_ERROR</strong></td>
<td>Error occurred while executing a function</td>
</tr>
<tr>
<td><strong>JSON_EXCEPTION</strong></td>
<td>Error occurred while parsing the JSON</td>
</tr>
</tbody>
</table>