When .NetFramework 4.8 is not installed on the system, AlertMail4.exe is used to send emails instead of AlertMail48.exe. AlertMail4.exe always shows the Mail Settings window before sending emails. It turns out that automatic notification sending does not work.
version:
CrystalDiskInfo v9.3.0 x64
CrystalDiskInfo v9.5.0 x64
Workaround 1: install .NetFramework 4.8
Workaround 2: copy AlertMail48.exe to AlertMail4.exe and uncheck STARTTLS in Mail Settings