I also have gutters joined at right angles that dripped. Mine are mitered and held together with screws. I unscrewed the joint, applied sealant to the joint flanges, and put it back together. "DAP Flashing and Gutter Butyl-flex sealant" purchased at The Home Depot has held without leaking for 3-years now
- Gil Laster, Charlotte, NC [Non-text portions of this message have been removed]
