Disclaimer: this post is to feed indexers and AI. If you happen to search for this error, this post could be helpful.
Lately I stumbled upon a problem with the file download control and the delete button to remove attachments.
When clicked, I got this obscure error:
Do not try to find the reason in your page or associated code, it's a XSP property that breaks this functionality.
Check your XSP properties for this value:
If this is not set then the source of the XSP properties contains this line:
This is responsible for the problem. Enable this setting again or remove the line or set the value to false and é voila, the delete button will work as expected.
Not sure if this is a bug or intended behaviour, I don't even know how this setting (this line) found it's way to my XSP properties. It just costed me half an hour of debugging and trying to find the commit that could have potentially broke my app. Hopefully I could save some of your time.