Get a 403 error when adding an image to the online registration page in event management

Question

Using CiviCRM 4.6.6. on Drupal 7.56

Just moved this site to a new server following normal procedures.

When managing an event, I can add an image to the info and settings page, but when I try to add one to the Online Registration page, the registration page is returned incorrectly and I get a 403 error. The event ID is completely lost. This is intermittent. Sometimes the page saves the image.

Trying again on 4.7.22. Endless spinning triangle of death.

Any ideas? Thanks

Answer 1

Turns out it's ModSecurity on the server interfering with things.