From the Reference section of the My Information box on the My Profile page:

- To update the reference's information, click on their name, edit, and click Save Changes.

- To add a reference, click "Add Reference" on the Reference page.

- To delete a reference, check the box next to the reference’s name and click the Delete Checked button. Please keep in mind that this information cannot be retrieved, and that this will not delete the reference from the list that you already submitted with any applications.

- To update a letter, click on the name of the reference, once you click on the name of the reference scroll down to the letter of recommendation section. There you will have two options. Option 1 is to copy/paste the new letter into the box and select Save Changes. The second option is to upload a new file. If the original letter is locked, please send your reference a request for a letter update. If the letter was uploaded, you can delete the letter from the Attachments section and then upload a new letter or request that your reference do so.
