Is there a way to change a software (not system) trayicon for example a download manager or something like that (i'm trying to change Mipony tray icon).I took a look to the forum but i didn't find what i'm look exactly for.
If you mean the icon that Mipony shows in the tray I think the only way would be via a resource editor. Usually the application uses its standard icon for the tray also. But it doesn't have to. Typically you would replace the first icon in the exe file. But some programs may use a different icon for the tray. You can open the exe with a resource editor and look.
Just be aware that if you make a mistake you could overwrite something in the program. Also I don't know if there's anything that prohibits doing it. Seems unlikely though.
If I don't have the idea what you want to do please post and correct my impression.