I was recently asked to assist a co-worker with an issue he was having with Microsoft Project. He was working on a rather large implementation plan, and needed to assign the first 2/3rds of the tasks using the typical 8-hour day/40-hour week calendar, but the last third (and of course the most critical) were to be done across three 24-hour days. While this seemed like a common enough scenario, especially for large application upgrades and installs, MSProject was balking at allowing us to set this up. It was another case of “I know what I want to do, but I don’t know how”.

After much searching of the help files, google-ing and otherwise gnashing of teeth, we found the answer.