..., then there's really not much that can be done, and the request will have to be ignored until such time that a logo/icon can be provided. An icon of appropriate resolution can be provided or linked to. Ideally, the provided file will be a vector file (e.g. SVG, EPS, AI) or a PDF with the vector file embedded. These files are all very easy to work with, and result in the most faithful reproductions of the icon.