Is it legal to extract icons of other software installed in my computer to use in my own software?

Anyone please shed some light on this question?

Normally you have not right if the software is copyrighted. Especially, if you plan to redistribute extracted icons in your own app. You have a lot of websites that offer icons that can be used. For instance, in PNG format. You can then convert them to .ICO (with different icon image sizes) with GConvert.

Thank you. Such a nice tool, bought it.