That’s a problem if you think permanent pens are permanent, but they aren’t.
Here’s a quick tip on how to clean permanent marker ink from a white board and other smooth surfaces.
All you need is a dry erase pen! Just “erase” the permanent ink with your dry erase pen, then wipe off the dry erase pen marks and you’re done. That is, if you are working with a perfectly smooth dry erase board. If it’s scratched, go over it again with window cleaner and you’ll have your white board back to new!