How to remove the error"no valid MBOX files"
One of the common error which occur during import or recovery of MBOX files is "no valid MBOX files were found". But, it can be fixed using a suitable method.In general, there are two ways to fix this error.
One is manual method in which we first locate the .mbox file in the root folder for the mailbox directory and then follow the procedure guided by wizard which appears on additional screen.
Another method is to use a software tool which imports MBOX file. It recovers the corrupt MBOX files and also converts them into other file formats like MSG, NSF, PST etc.
For more info, you can read this article.