One of our viewers had left masking tape on the aluminum siding around a window far too long and it didn't want to come off without scraping, like you can see in the photo. Any oil, even vegetable oil, will serve to soften the old glue and allow removal, but the most efficient remover we found was a product appropriately named Goo Gone. It didn't affect the aluminum painted finish at all.
Masking tape should never be left on any surface for more than a couple of days, and certainly not more than a single day in sunlight.
I hope you got it clean Shirley.
Goo Gone from the company Magic is a standard hardware store product. We also used vegetable oil and Release All penetrating lubricant.