Does the questioner want to ask "What should I do if mini4 cannot install 15.6.1"? .

1. The download location is wrong, the installation package is wrong, and the storage is insufficient.

1. 15.6.1 cannot be installed through some third-party software downloads: If the software downloaded from the third-party application store cannot be installed, it is recommended to bind the APPLEID on the mobile phone to re-download and install it.

2. There is a problem with the 15.6.1 installation package: for example, it is incomplete or the signature is inconsistent. In this case, you can try to re-download it through Synchronous Push and then install it.

3. The mobile phone storage space is full: clean up the mobile phone memory, delete uncommon software and try installation again.