1. A method for restoring an occluded window in application sharing, comprising the steps of: detecting that an unshared window occludes part of all of a shared window; in response to said detecting, (a) creating a first alpha blended image by making the unshared window semitransparent by an alpha blending operation, using a first value for the alpha factor; and (b) creating a second alpha blended image by making the unshared window semitransparent by an alpha blending operation, using a second value for the alpha factor; and restoring the occluded shared window by using the first and second alpha blended images.