Java Script Error

I’m trying to solve a problem for an end user. They are getting an error message when they click on delivery options in a new mail message. They first get an error saying “A JavaScript Error was encountered. Error: ToObjectError: window.opener has no properties.” They can close this window and then a delivery options window pops up (but not the normal one) which they need to cancel as well.

They are working from a local replica mail file. If they work from their mail file on the server, the error does not occur.

I’ve tried creating a new replica, but the problem still exists.

I’m not much of a programmer/designer, so not sure what else to check. Have not noticed anything else not working on the local copy. Tried the basics such as new notes.ini, deleting bookmark.nsf and cache.ndk, but no luck

Any ideas? Thanks