Error 3120 (Previously Error 112) indicates that JDM Pro does not recognize the device that the recipient originally registered.
Firstly, all recipients will show Error 3120 for up to 5 minutes after the recipient is created. This happens because it takes time for JDM Pro to calculate all the current versions of all content assigned. If you see this error on a newly created recipient, you only need to wait a couple minutes and try again.
If the error appears in any other scenario besides a brand new recipient, the resolution is always the same:
- Deactivate the device
- Open the app and confirm deactivation
- Click the activation link in your registration email to re-register your device and re-download content
If you are using multiple Jeppesen/Boeing apps, please check your Limit Ad Tracking setting.
There are several different things that may cause this problem and it is often difficult to determine exactly why it occurs. Below are some examples of what may cause this.
- Jeppesen/Boeing Apps are designed to only work on a single device per recipient, however, that recipient can register multiple times with the same link. Each time the recipient registers a new device, the previously registered device can no longer update and reports Error 3120. Sometimes, a recipient may forward their link to a personal device to use as a backup. It will appear to work, but when it comes time for the next data update the first device will fail and report this error code.
- Similarly, if a recipient changes their device or changes their iCloud settings or iCloud account this error may appear.
- Improperly registering a Jeppesen/Boeing app after one is already registered on the device. The proper way to activate additional Jeppesen/Boeing apps after one is already activated on the device is to use the Share Registration feature. Registering subsequent apps using the registration link instead of Share Registration will cause this error in all Boeing/Jeppesen apps that were already on the device. This is due to iOS's "sandboxing" which prevents apps from interacting with each other, the newly registered app appears to be a completely different device to JDM Pro which causes the error.