Applicants are not be able to upload letters of reference themselves. However, letters of reference that are sent directly from the applicant to CaRMS may still be processed, specifically when an applicant has immigrated to Canada with the letters in their possession and no longer has the opportunity to have a letter submitted directly by the referee.
If you feel this situation applies to you, you must create a reference request for the letter of reference(s) in your CaRMS account.
To create this reference request, go into the "My Documents--> Reference Requests" section of your CaRMS Online account and a coversheet will be generated. You will need to email this coversheet, along with the letter of reference to email@example.com