Applicable to End Users
When installing or upgrading the app, the "Untrusted Enterprise Developer" message is displayed. To overcome this issue, you must install a developer certificate and trust the enterprise that created it.
Open Settings on your iPhone.
Tap General > Device Management.
Click the enterprise app for which you must trust the certificate.
Tap Trust "<enterprise-name>" and then tap Trust on the pop-up window.
The Trust certificate is activated.
In case you do not trust an app, you can delete it from your iPhone.