this seems to be the same issue reported as fixed here:
however – testing in 4.7.3 in Joomla and Drupal (haven't tested WP yet) it is still broken.
to reproduce –
- create a custom field set in a tab
- create a custom field of type file
- add the field to a profile
- visit the profile and upload a file
- visit the contact in the admin side and click the custom data tab
it errors with "one of parameters (value:...) is not of the type Integer.
this renders the entire custom data set completely unavailable. I would view as a pretty critical issue as anyone with existing custom file data will not be able to access the record via the admin side.