Unable to install or download the app

This family of errors sits between transport and package verification. Find out how far iOS got.

No install prompt appears

Suspect the signer or website's installation trigger: invalid manifest URL, non-HTTPS endpoint, local server not running, VPN/DNS interference, browser restrictions, or a signer still compressing the IPA.

When the Install button does nothing, the network is the usual cause: an ISP filter, ad blocker, VPN or DNS profile blocks a host the install needs. Switch between Wi-Fi and mobile data, or use a public DNS such as Cloudflare's 1.1.1.1 app, and try again. Turn off any anti-revoke DNS profile while installing.

For enterprise-style OTA distribution, Apple requires an HTTPS website, XML manifest, correct MIME types, and accessible IPA URL (Apple Platform Deployment).

Icon appears but progress fails

Check free storage, bundle structure, device UDID, profile validity, certificate status, nested signatures, bundle ID collisions, minimum OS, and CPU architecture.

Install stuck or icon stays grey

1. Force restart. On iPhone 8 and later: press and release Volume Up, press and release Volume Down, then hold the side button until the Apple logo appears. On a Home button iPhone, hold Home and the side button (iPhone 7: Volume Down and side).
2. Delete the stuck icon.
3. Install again.
4. If it sticks a second time, get another copy of the IPA. The file is the likely problem.

Install completes but app cannot open

Move to trust, Developer Mode, expiry/revocation, or runtime diagnosis. Installation success does not prove launch compatibility.

Isolation test

Use a small known-good open-source IPA with the same signer and certificate. If it installs, focus on the original IPA. If every IPA fails at the same point, focus on the signing pair or transport.

Do not delete a data-bearing app until you have tested with another bundle ID or made an app-level backup. Do not install broad DNS profiles to fix a malformed signature.