In order to be able to add an Event to a friend's calendar, the owner of the calendar will need to give you Edit Rights to that calendar. “Edit Rights” are the ability to make edits to your content in your account that you can give to anyone in your Share List in the Share Control.

When you share anything that you have created in Keep&Share, there is a column in the Share Control labeled “Allow Edit” with a check box next to each name in your Share Control. When you click on these check boxes, you are giving people the ability to changes and make edits to items in your account.

By default you are the only person that will have the ability to edit any of your content on Keep&Share. You will have to go into the Share Control to give anyone else Edit Rights.

However, in order for Edit Rights to work, both the person sharing Edit Rights and the person doing the editing need to have paid accounts. You can share a calendar with anyone – even the public or with free accounts – but to collaborate together on a calendar's content, you both need to be at the same plan level. Learn more about Edit Rights.