---
title: "App Installation & Configuration"
description: "Resolve common Marketplace app setup issues, including JSON type errors, installation limits, disabled save buttons, and managing settings during re-installation."
url: "https://www.contentstack.com/docs/marketplace/app-installation-configuration"
product: "Contentstack"
doc_type: "guide"
audience:
  - developers
  - admins
version: "current"
last_updated: "2026-05-11"
---

# App Installation & Configuration

## 1\. App Installation Fails with "Type Error" (Invalid JSON)

Users encounter a TypeError during the installation of Marketplace apps when the configuration parameters do not match the expected JSON schema. This often happens when a string is provided where a JSON object is required.

**Resolution**

1.  Review the app's configuration documentation for required field formats.
2.  Ensure that complex fields, such as proxies or custom headers, are wrapped in valid JSON curly braces {}.
3.  Validate your JSON input using an external linter before saving the app configuration.

**Verification**

The app saves successfully, and the "Installation Complete" message appears without console errors.

**Note:**

If valid JSON still triggers a type error, provide the configuration snippet and the specific app name to the support team.

* * *

## 2\. Marketplace App Limits: "Maximum Apps Installed"

A "Limit Exceeded" error appears when trying to install a new app from the Marketplace.

**Resolution**

1.  Review your current **Subscription Plan** to see the allowed number of Marketplace app installations.
2.  Uninstall unused apps to free up slots for new installations.
3.  Contact your account manager if you require a limit increase for your organization.

The "Install" button becomes active after removing an existing app.

* * *

## 3\. Marketplace App "Save" Button is Disabled

Users cannot save changes to app configurations because the "Save" button remains greyed out.

**Resolution**

1.  Ensure all **Required Fields** (marked with a red asterisk) are filled.
2.  Check for validation errors in input fields, such as invalid URL formats or out-of-range numbers.
3.  Verify that you have "Admin" or "Owner" permissions for the stack.

The "Save" button becomes blue/active once all validation criteria are met.

* * *

## 4\. Missing App Settings After Re-installation

When an app is uninstalled and then re-installed, all previous configuration settings are lost.

**Resolution**

1.  This is expected behavior; app settings are stored per installation instance.
2.  Before uninstalling, manually back up any complex configuration JSON or API keys.
3.  Use the "Update" feature instead of "Uninstall/Reinstall" if you are just changing versions.

The new installation is configured using the backed-up settings.