Inspect the vinyl side hook by holding it up beside another that has no damage. The lip that slides underneath the siding often is bent due to hanging a heavy object on it. Another section that may show damage is the hook itself.
Place the vinyl siding hook on a hard, flat surface, such as a concrete porch, driveway or a sturdy worktable that a hammer won't damage.
Tapping the lip or hook edge gently with the hammer molds it back into the original shape.
Sliding any rounded sections of the vinyl siding hook over a piece of metal pipe lets you hammer it back into a proper curve. Some vinyl siding hook types have an S shape. The metal pipe provides a curved form for use, as you shape it back into place with the hammer.