Clicking "COX" in the upper left corner of the Webmail Inbox directs you to the My Profile home webpage. From there, you should be able to access Voice Tools Call history by clicking: My Account > My Account > Call history. However, it doesn't always work for me and it may not work for you. Some times after I tried that, I was also unable to access call history from https://phonetools.cox.com/history.
If you get a blank screen, the wrong screen or the "Bad Request" error when trying to access Call history, do the following:
1, Delete "cox.com" cookies
2. Close the browser
3. https://phonetools.cox.com/history