If your windows are icing up or condensing more than normal it is likely that one of two things has likely changed. First of all ask yourself if you have produced more humidity lately that could cause the windows to condense. A cold can of Pepsi on a warm day is an example of condensation. When the cold air meets the warm at the window it condenses. If your home has high humidity such as steam from cooking or several other sources this might be the problem. A second factor may also be at play. Have you recently added or changed the position of your blinds? If you close your blinds you impede air circulation over the window surface and ice often forms. You can also try running the principle air fan if you have one.