EXE Icon Recommended size

Hello
I would like to use GConvert 5 to create an EXE icon from a png (or other formats). Is there a recommended size to be used for the output icon please?
Thank you

Dave

wrong post, sorry

In the “Import Picture” editor, choose a 256x256 image for your future icon.
Then, in the editor, click “Generate Other Images” and click “Add Vista (default)”.
Save your icon. It is ready for XLS Padlock.

Took a while to locate the “Generate Other Images” but appear to have got there.
Thanks.

Dave