At least one client task has invalid configuration and therefore will fail

[FriggGuðrún 5]

I receive an email warning about this every hour or so.  It's been happening since late last week.  Logging into protect.eset.com I see the number "20" next to the detections icon.  When I click there, I get a list of 262 notifications, but these have all been marked as resolved.

It doesn't seem to matter how I filter the search, I cannot clear that "20," nor do I see 20 new detections.

What is the best way to root out this error "At least one client task has invalid configuration and therefore will fail"?  

[Marcos 4,705]

Please post a screenshot of the error since it doesn't ring a bell with me.

As for the detections, you can't really remove them but you can hide already resolved detections via the appropriate filter:

[FriggGuðrún 5]

Screenshot:

[Marcos 4,705]

I'd suggest that you open the Tasks panel, select Client tasks and apply a filter for invalid tasks as per the screenshot below:

You should get a list of invalid task along with a reason.

[FriggGuðrún 5]

When I filter with the "is valid" filter checked, I find a list of valid tasks.  A couple of them have some yellow splats, but there is no flag indicating what invalid task is out there.