You need to provide DIGITAL signatures (not electronic ones) on pages 3, 4 and 8 of the form. Page 3 is the sponsor's signature, Page 4 is the applicant's, and page 8 is the Sponsor AND applicant.Oops. Sorry wasn't able to add screenshot with the post. Here's what CIC said in the letter.
IMM 5532 Relationship Information and Sponsorship Evaluation: Please provide a
completed and signed Relationship Information and Sponsorship Evaluation (IMM 5532) Form.
The Sponsor and Principal Applicant should complete the form and sign the declarations
where indicated.There are (4) mandatory signatures on IMM 5532 throughout the (8)
pages of this form. All signatures are mandatory and
required.
http://www.cic.gc.ca/english/pdf/kits/forms/IMM5532E.pdf
As it does not meet the requirements for processing, your submission and documents are being
returned to you and will not be processed or put in the queue for processing
That's what they mean by four signatures. Remember they have to be actual signatures (which you can create using computer software). I know it's a pain, but that's what they want.