MS-SQL/ColdFusion: Mysterious database error: Object has been closed

This is old, but I just ran into this and found a way to do it without restarting CF.

In the ColdFusion Administrator go to your Data Sources and edit the one that's causing your problem. Make a change in it, like checking an unimportant box, and Submit.

This will reconfigure the connection and allow it to work. Go back in and un-tick the box (if you don't really want it ticked).

For example. I turned off "Enable High ASCII characters..." hit submit and the datasource worked. I then went back in and checked it back off and submit the changes again.

No restart! Ideal if this is a production box.

We ran into this problem with CF9 and restarting the service didn't help. We deleted and recreated the offending DSN in the CF configuration, and that has resolved the issue. So if the other solutions don't work, give this a try.