Recently, scheduled reports stop sending the reports to email group after OS patches. Below message is for your reference.
Exception: java.io.IOException: Need at least one of
"to", "cc" or "bcc" address:
After doing some analysis we found that emails are going to individual members of the group instead of email group for those groups which are populating email addresses and giving above exception for those email groups which are not populating any member of the group.
You can find the email members of the group while specifying the recipients of the report. Pressing <CTRL+SPACE> activates proposals.
Looking forward for your as usual valuable input.
We found a root cause of this issue.
If we import an AD Group and schedule a report for that group then users of the group should be login/access Dynatrace Server minimum once to populate in the group and be a recipient for a scheduled report.
Sometimes a group of users just need a report e.g. business user and management user, etc. so in this situation we should use the email address of the AD Group instead of a Group Name.