Updating Images

When I am working on an email and want to change an mage almost invariably when I click on "replace image" Nothing happens. I have to log out, then log back in and then it works. But the next time I want to change another image the same thing happens. Unbelievably annoying. I have tried Chrome, Firefox and Safari. All have the same problem. So I have to believe this is a Constant Contact issue unless it has to do with my three year old Apple desktop.