Hi Nancy, I would not advise using caulking, I fixed my leak by myself with glazing, I use caulk for everything but the clerk at my local hardware store reminded me if it is not fixed right I would have to replace my whole window :(( So I bought Dap glazing and a putty knife and did it myself,, I used a heat gun to soften the old glazing and scrapped it all out then I mixed a baseball size of dap with 1 Tbs. talc powder in my hand and kneeded it well and rolled it into a snake form and pressed it in, then I dipped my putty knife in mineral spirits and smoothed the putty at a 45 degree angle making sure it was pressed up against the window good. Let that dry for 2 weeks then use a good primer/sealer, I used bin. It is time consuming but much cheaper than replacing the entire window. Good Luck :))