Problem
You are using the PRO version of Open User Map and try to import locations with the Import/Export Feature. The upload of the CSV file fails with the message:

Solution
This error happens because of security restrictions from WordPress itself. It doesn’t allow HTML in a csv file upload.
To override this add the follwing code snippet to your wp-config.php file:
PHP
define( 'ALLOW_UNFILTERED_UPLOADS', true );
I would recommend to remove this code after you are done with the import.