About once a month the links to our images within the Media module disappear. There is no error, the information within the Media module for the link to the image file is simply blank. The images are all stored within an images folder in the Admin's File Manager. This happens to all of the Media modules on our (child) portal at one time, so it does not appear to be user error updating one.

Once, we found that the permissions to this folder had been changed (not by an admin) so that All Users did not have Read access. We have sinced fixed that, but still the path information to the images were wiped out.

We do not have any monthly scheduled events that coincide with the 'droppage'.

The client is loosing confidence in the site as we are having to constantly check it for dropped links and re-enter them

Exactly the same is happening to a site I have built (DNN 4.9.2). The site is deployed on a webfarm configuration.

Are the steps you suggest a solution to this problem? Is it a known problem? Is there any documentation on it anywhere, please?

In addition to the above, all the image path and directory permissions need to be re-set.

We have noticed, that the scheduled file sync is not reliable, it has been removed in DNN 4.9.3 and above.

There have been no issues reported with auto file sync ore manual (recursive) file sync.