The default user and password is :
Username: admin
Password: admin
but if it didn't work you can reset the passowrd again by do the following:
1. Open Windows Explorer on the computer where you run Symantec Endpoint Protection Manager.
2. Change directory to the <Drive>:\Program Files\Symantec\Symantec Endpoint Protection Manager\Tools folder.
3. Double-click the Resetpass.bat executable file. The password is reset to the default password.
4. Be sure to change the password immediately.
** Note : Please mark it as solved if this solve your issue
.