I have an interesting issue. I am getting the error, "Error loading callback data" on my test site and my live site, however I am not getting the error on my local development site.
The error occurs when I try to set the Root Folder for the DMX module in the module settings screen. If I try to exapand a folder or select a folder I get the error.
I have been messing around to see if I can get it working and at one point the comboboxes did not render and instead I got a message that componentart was unlicensed and it prompted me to download a trial license. I navigated away from the page and came back and I haven't seen the unlicensed message again.
I am using a modified source for DMX version 5.0.2. I have not modified the this particular .ascx file.
Below is a screenshot:
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Thanks for the help,
Stuart