Question pdf not loading in 5.1.5

I've read several posts about this, but am not seeing a definitive explanation or fix.

When attaching a pdf as an attachment in a posting, it will not open or download. This happens when I insert a link for it or click the button for it.

If I clear the filetype attribute from the database table (kunena_attachments), it works fine.

We tested in Chrome 69.0.3497.100 on Mac and Windows.

Actually, its the same issue in another thread.
". The URL points to

media/kunena/attachments/<userid>/<real filename> and end up in error 404

In my understanding they should be something like

.../attachment/<attachmentID> as it is also shown on images. Manually using that link works.

Something seems wrong with $attachment->getURL method . It happens in attachment info, attachment button and in embedded link in post text.
"

How do I fix this?

This is the default path to attachements: If not, there is something wrong with your installation or your browser. Test with Firefox.

Yes. That is the correct path. The files in that location aren't listed by the filename_real, but rather the filename. For example:

Oct 26 18:41 929dcaa827fce41b577a850802f8c5ae and the filename_real is example.pdf

In the database, that corresponds to the correct filename_real value, but the url attempts to load

/media/kunena/attachments/user-id/example.pdf and it gives a 404 error

If I load this:

/media/kunena/attachments/user-id/929dcaa827fce41b577a850802f8c5ae

It loads fine.

Just jumping in to say I am getting the exact same problem. Attachments have been working fine.. but users now getting these 404 errors when they try and open them.

It's caused by enabling protect attachment in Kunena configuration. Might be a bug.