Currently when the MySQL DB user does not have the "create temporary table" grant/permission set (a new requirement we introduced in Matomo 3.12.0 or so), the archiving of reports fails with a cryptic error message, as reported by several users in the forum.
The message says
SQLSTATE: Syntax error or access violation: 1044 Access denied for user 'abc'@'localhost' to database 'matomo' - in plugin Goals so it's not clear what the problem is.
Ideally when the user does not have the right permission:
GRANT CREATE TEMPORARY TABLESand maybe list the command to execute directly, or link to a new FAQ or our FAQ explaining the command to run