Queries can fail with the error message:
Query was rejected based on a rule that did not specify a rejection reason.
This is usually caused by one of two reasons.
1 - Not matching any rules
If the query does not match any of the rules that have been set up to route queries to specific queues, it will fall through to the last rule, which by default will simply reject the query with no defined message stating why.
2 - Matching a Reject rule
If customised rules have been put in place, it's possible that the query matches one of these additional rules. If the action for that rule is set to Reject and nothing was entered as a Reason for this rejection, the behaviour described above will be seen.
Examples:
1 - Not matching any rules
If the default rules for matching against the cost of a query are changed, leading to a 'gap' in the ranges of allowed costs, a rule can slip through and not match anything.
E.g. if the Low Cost User Queries rule is adjusted downwards without also adjusting the High Cost User Queries threshold:
2 - Matching a Reject rule
A rule can be added to reject any query above a certain cost threshold. E.g.: