Possible reasons are:

1. There is a problem with the mobile phone settings. Enter the mobile phone settings to allow installation.

2. The software is not signed or the signature is incorrect. Just re-sign it.

3. Certificate conflict, you can only reset and try again.

The specific troubleshooting methods are as follows:

1. There may be a problem with the installation package of the software, causing an installation error. You can re-download the complete installation package; the mobile phone settings do not allow installation from unknown sources. package and reset.

2. It may be that the mobile phone system has insufficient storage space, causing errors in software installation. You can uninstall software that is not commonly used on the phone, or use a cleaning tool to clean up the cache data and junk files generated by the system and software. After freeing up more system storage space on your phone, you can install software normally.

3. It may also be a system problem that causes an error when installing the software. You can try restarting the phone, or restoring the phone's system to factory settings.