My colleagues and I encountered a problem with a file, so we delivered a changeset but that caused an error. We tried to reverse the change so we could recover the file. This worked, but now we want to see if we can recover the changeset history. Is this possible?

It should be possible to view the changeset history of the file in question by going to the explorer where you view the files (e.g Project Explorer view in Eclipse) right-click on the file, and select Team -> Show History. The last two entries should be the patch that the reverse operation created, and the deliver that required the reverse.

Another nugget that many people don't know: if you are trying to locate a change set that you know exists but isn't showing up in the current change history, the history view includes an option (accessible through the triangle dropdown tool at the top far right of the history view) which is called Show All in Repository.  This will also allow you to locate potential conflicting changes that another developer may be making in their repository workspace before they even deliver it to the stream (i.e. a future potential conflict).

intriguing, thanks