Another questions: -
- how many categories and folder have you?
- on which page (in jDownloads) see you this message?
- the other pages in jDownloads work as expected?
- what have you selected in the Joomla configuration for the option: 'Error Reporting' (see pic)
Since it appears to be a problem with the php coding....
Yes, possible. But with your modifications or the original source code?
As example, you use an old version. Your version 3.2.46 current version 3.2.51.
The error message at the end from your pic was fixed in 3.2.47.
So you should at first use the original bug fixed file (below). Then we can check the result.
Copy the unzipped file downloads.php
But you should prior rename the original file.
Should this not help please send me login data via PM.