Clean the windows well on the inside and outside with glass cleaner. Wipe the aluminum wraps with a rag dampened with plain water. Let the windows dry completely.
Scrape away old caulk and paint between the window wraps and surface behind with a putty knife. Examine the area and make sure it is free of debris.
Wedge the tip of the opened caulk into the space at one end. Hold the caulk at a 45-degree angle and squeeze the trigger of the caulk gun. Move the caulk along the opening to fill it with a long, continual application.
Fill the rest of the spaces with caulk as you did the first. Push any caulk that overflows the space back into the area with the blade of the putty knife. Let the caulk dry completely and add more to any areas with remaining space.