You must provide at least one recipient email address error.

I constantly encounter these errors in the eventlog section, about 200,000 events were caught in this way.

mail examples :,

Is there an easy way to fix it? For example, can’t we delete them when we load the data?

It seems that the system doesn’t recognize these values as an email address. to troubleshoot, I would look the emails up in the system, and see what their subscriber profile looks like. (Subscribers, Search subscribers).
My first hunch is that somehow the record was imported improperly, or has some kind of character in it that causes the system to not recognize it. This would happen if imported properly, if the character coding on the server is incorrect, etc…