Screen unlock PIN has no submit button on Lenovo TB-X306F: PIN auto-submits after 4th digit

Android

If you're having trouble unlocking your Lenovo TAB M10 TB-X306F device after provisioning it with Esper, this article explains the issue and how to work around it.

Understand the issue

On newly provisioned Lenovo TB-X306F devices, the Esper Agent screen unlock prompt does not display a visible "Submit" or "OK" button. However, the device will automatically unlock after you enter all 4 digits of your PIN.

This issue affects only newly provisioned TB-X306F devices. If your device was already working before this problem appeared, do not re-provision it—re-provisioning will introduce this behavior.

How to unlock your device

On the lock screen, enter your complete 4-digit PIN without pressing any button after each digit.
After you enter the 4th digit, the device will automatically unlock.
The device will proceed past the lock screen and load your managed home screen.

If the automatic unlock does not work

If your device does not automatically unlock after entering 4 digits, it may be fully blocked. In that case, collect a bug report immediately:

Follow the steps in How to collect device logs and bug reports.
Contact Esper Support and provide:
- The bug report from your affected device
- Your Esper Agent version. To find this, go to Devices & Groups → [Your Device Name] → Device Info → Agent Version
- A screen recording showing the missing submit button and PIN entry behavior
- Confirmation of whether the automatic unlock worked or failed

Avoid re-provisioning working devices

If you have a TB-X306F device that is already working, do not re-provision it. Re-provisioning will apply the newer Esper Agent version and introduce this unlock issue on your device.

Still need help?

Contact Esper Support if the automatic unlock workaround does not work or if you need additional assistance.