How to Fix “App Integrity Could Not Be Verified” on iPhone (Scarlet)

You install an app through Scarlet, tap its icon, and iOS stops you cold: “App integrity could not be verified.” Unlike most Scarlet errors, this one is not really about trust settings — it means the app itself failed iOS’s signature inspection. This guide explains what the integrity check is actually checking, how this error differs from the similar-sounding “Unable to Verify App,” and the fixes in the order most likely to work.

What “Integrity Could Not Be Verified” Actually Means

Every iOS app carries a code signature — cryptographic proof of what signed it and that its contents have not changed since. Before launching an app, iOS validates that signature. “Integrity could not be verified” means the validation failed. The usual reasons:

• The signing certificate is revoked or expired — the signature chain no longer leads to a currently valid certificate.
• The IPA file is corrupted or incomplete — a partial download changes the app’s contents, and the signature no longer matches them.
• The app was modified after signing — tweaked or repacked IPAs whose contents were altered without a proper re-sign fail integrity by design.
• Mismatched signing pieces — a certificate and provisioning profile that do not belong together produce an invalid signature.

Integrity Error vs. “Unable to Verify App” — Not the Same Error

These two messages get confused constantly, and they need different fixes:

• “Unable to Verify App” means iOS could not complete the online check of the developer/certificate — a connection or trust problem. Fixes live in our unable to verify apps guide.
• “App integrity could not be verified” means the signature on the app itself failed validation — a certificate-status or file problem. Reconnecting to Wi-Fi will not fix it; the app must be re-signed or reinstalled correctly.

The Fixes, In Order

1. Check whether the certificate is the problem

If several Scarlet apps started showing this error at the same time, the shared certificate was revoked — nothing installed under it will pass integrity again. Check the current situation and your options on the certificate status hub, then reinstall Scarlet under a working certificate.

2. Delete the app and reinstall it cleanly

Delete the failing app completely (not just off the home screen), restart your iPhone, then reinstall through Scarlet. A restart clears cached validation results, and a fresh install eliminates a corrupted first attempt.

3. Re-download the IPA from its original source

If only one app shows the error, suspect the file. Download the IPA again from its original source — not a re-upload or mirror — and install the fresh copy. Even a small download interruption corrupts the signature match.

4. Set date and time to automatic

Certificate validation depends on your device clock being correct. Go to Settings → General → Date & Time and enable Set Automatically. A manually skewed clock makes valid certificates look expired.

5. Remove duplicates with the same bundle ID

If you previously installed the same app (or a modified variant) from another source, delete every copy before reinstalling. Two apps fighting over one bundle identity produce signature conflicts that surface as integrity errors.

6. Re-sign with a certificate you control

If you imported the app with your own certificate, the certificate/profile pair may be mismatched — re-import them as a matched set, exactly as described in the custom certificate guide. If you rely on shared certificates, signing your must-have apps with your own certificate (in Scarlet or a signer like ESign) is the permanent fix for this entire class of error.

7. Try another installer

If an app refuses to pass integrity under Scarlet no matter what, install it through one of the Scarlet alternatives instead. A different signing path sometimes succeeds where one tool’s signing fails.

How to Stop This Error Coming Back

• Download IPAs only from their original, trusted sources — file integrity starts at the download.
• Sign the apps you depend on with your own certificate rather than shared ones.
• Avoid “pre-tweaked” IPAs from random upload sites; improperly re-signed files are the top cause of this error for single apps.
• Keep date & time on automatic permanently.

FAQ

Does this error mean the app is a virus?

No. It means the signature did not validate — most often a revoked certificate or a corrupted download. It is a signing problem, not a malware verdict. (It is still a good reason to only install IPAs from sources you trust, as covered in is Scarlet safe?)

Why did all my apps get this error at once?

A mass failure at the same moment means the shared signing certificate was revoked. Every app under it fails integrity together. Reinstall under a working certificate.

Will trusting the developer profile fix the integrity error?

No. Trusting the profile handles the “untrusted developer” prompt. Integrity failure is deeper — the signature itself is invalid, so only re-signing or reinstalling under a valid certificate fixes it.

The error appears for one app only. What is most likely?

A corrupted or badly re-signed IPA file. Re-download that app from its original source and install the fresh copy before trying anything else.