Thanks Sarkut/Ego Eram Reputo. I dragged the extracted files into the Effects folder, restarted and I can now use the Perspective tool. Unfortunately I cannot achieve the desired effect which is to correct a distorted image in which the right side slopes to the left and the left side to the right although by a lesser amount. I can do this easily with Photoshop Elements 6 when the image is surrounded by a bounding box with nodes at the corners which can be dragged independantly to make the image sides vertical. I do not want to use the Adobe software which was expensive to buy and to upgrade. Elements 6 was not compatible with Windows 7 and they expected me to buy Windows 8. I accept that this method is not possible with Paint.Net and would be happy to use it if I could get the required result. There are 24 different combinations (3 Ratios; 4 Vertical,Horizontal,Perspective and Trapezoid; 2 Linked or not). I have tried all 24 but cannot achieve a rectangular image of the correct proportions. DPY's method has received a lot of high praise which makes me think it is me. Whatever, I will continue to use and enjoy Paint.Net.