Unable to remove attachments in UWL

Hi All

When I upload a new file to the UWL Task using 'Manage Attachments' option and I want to remove it, the 'Remove' button is disabled even for the file that I have uploaded.

This is working fine in Dev. We are facing a problem in QA only. I assigned all the authorizations the user had in DEV in QA too, and it still didn't work. Is there any dependency on the type/status of task and the ability to remove attachments in UWL?

Thanks

OJ