Error when using IMAP Roundtrip sensor.
Cause: Port 465 or 587 closed
Solution:
1) Need to open this port
Port for SSL: 465
Port for TLS/STARTTLS: 587
or
2) Turn ON setting “Allow less secure apps” dalam GMail Account
Refer: https://support.google.com/mail/answer/7126229?visit_id=1-636271485504237731-3787438172&rd=2#cantsignin