subsequent window sealing

Since our window installer executed the inner sealing poorly, after much frustration we have decided to do the sealing ourselves. The sealing tape of the inner sealing is leaking in some places between the window frame and the wall at the frame. Do I need to remove the window to make the sealing tape watertight again, or is it sufficient if I apply a seam between the window frame and the sealing tape with the film adhesive? There might also be the possibility to stick the tape on the front side of the window if it is still covered by the plaster. What would you recommend?

Hello, there are already several threads on this topic... But: The "Kompriband", which is applied around the window before installation, then expands after installation and can perform several functions (airtightness, insulation), cannot be applied afterwards without removal. Fortunately, there are different ways to achieve the goal. Also, a sealing tape attached to the window frame can help to separate the indoor climate from the outside. That’s what it’s for. And yes, it would certainly be executed in the area of the reveal in such a way that it would be covered by plaster afterwards.

However, the execution may be somewhat different depending on the construction method. I only know the one required for "our" wooden frame or solid wood construction. It mentions plaster and it is about "inside". Presumably, you are building stone on stone?

Post several pictures of the "current condition" with enough details, then more can be said about it.