You may have done this, you may have been 'the one', if not, it will happen one day!
So there you are in the boardroom, discussing some concept, plan or code strategy. Someone doesn't quite grasp what you are trying to explain, so you think a quick drawing on the Dry Wipe board will help get the subject matter across. You stand up at the board, pick up the pen, and doodle way.........then it dawns on you, you have used a permanent marker that some fool has left near the board. Panic
Some fool has used a permanent marker on the dry wipe board in the meeting room, and you need it for the meeting you are away to host......
First off, do not get the chemicals out just yet it may make the situation worse. Get you hands on some paper towel, old cloth or some duster of sorts, and then get preferably a dark coloured, e.g., black dry wipe pen designed for the boards. Using a dark pen, means that you do not stain the tip of the pen, wrecking it for future use.
Commence overwriting the permanent marker with the dry wipe pen, and rub off as you go every couple of inches or so. The permanent marker should lift off as if it was never there in the first place.
[If this doesn't work, start running........ ]