How do you wash in the inside of a double paned window?

They should be sealed and you are not supposed to access in between the panes. Chances are they can be reglazed, contact a licensed window professional.

I think you have the kind of windows which move up and down. But when one moves, it covers another. The only way I have found, with many frustrating tries using bottle brushes, soaking wet dish towels, and sliced sponges, is to remove the upper half window from the door, wash everything separately, and put it back together. In one house, that worked great. In another, we had to replace the seal around the windows in the whole door. $1 fix back then. 😇💞

you cannot ,the seal is probably gone

If a double pane window needs cleaning on the inside, it has a broken seal. You can't fix that yourself. You'll need to call someone, like Naomie suggested. Sorry, it's expensive. Been there, done that.

If water or dirt starts to build up between the two panes, it is an indication that this seal has been broken. This break can be as small as a pinhole. In order to cleanbetween the two pieces of glass, the windows would have to be completely taken apart, which would really break the seal.

Thank you everyone!