Hi @James Frost,
Starting in 2019, all ancillary SQL Server components can be found at the Download SQL Server extended features and tools page.
I have not found the Service Broker External Activator for SQL 2022 as well.
And as someone said here, Service Broker External Activator service" is not provided by Microsoft after Sql 2017.
The error message is general to narrow down the issue, could you check the event viewer to see if there are more details.
You may also try to clean your Appdata\Local\Temp and make sure you have correct access there.
Regards,
Zoe Hui
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