10.14 in default is not "any source" option, the setup steps:
Step one: Applications - Utilities - Terminal
Step: Input terminal: sudo spctl --master-disable determination
The third step: Enter password: When you're finished, to confirm (can not see the password input process, Apple's protection mechanisms)
Step four: upper left corner of the desktop Apple - System Preferences - Security Privacy - Allow applications downloaded from the following location: Select the "any source"
Step five: can a normal installation.