Battery drains after two days and power widows don't work, tried replacing the fuse, out of ideas

 

More information? Start with the model year of the car. What fuse did you replace and why since there are a number of fuses. If the battery is drained, a whole bunch of things will not work, why focus on the power windows? Have you tried using an ammeter (a function of a typical voltmeter) to measure the current draw?

Since it's likely a bad battery or some form of short, some idea of the history of your car (i.e. I just pulled it out of a barn where it sat unused for three years) might be helpful.

Someone might be able to help if the problem/background is described sufficiently.

 

I have had similar problems with booth my Jags. Started after I installed a remote transmitting OBDII unit. Batt. continued to drain after removal of unit. Had to replace both Batt. one only 1 yr. old. I have been told problems arise using the OBDII units if they are not properly started and stopped??? Either Remote, or hand held.