Cannot display attachments in ArcGIS Pro

I’m trying to learn ArcGIS Pro 1.4, and with a little bit of pain I was progressing till today in which I cannot make my previous hyperlinks get ready in ArcGIS Pro. I think enabling attachments in first place and configure pop-ups afterwards might the be the right workflow to follow, correct?

I have reviewed the post: Work with file attachments, but it hasn’t helped me so far with this issue.

These are the steps I have followed so far:

i.e.: I have a point feature class, with some of the locations having associated files which I want to convert into attachments.

1. Analysis tab -> Tools -> Geoprocessing pane: Enable Attachments on the feature class that I want it to have hyperlinks functionality enabled.

This operation went well:

After doing this a relationship class and a table have been created in my geodatabase, OK.

2. Then, If I go the Attributes panel, Attachments, click +Add, when I pick up the file, it pop-ups an error:

What am I missing?