upey said:
I tried to send it but all the time i got the response that delivery failed permanently.
If emailing is not working then I would send the attachment via Case Specific Enquiry mentioning the attachment. It is also acceptable by visa offices to send documents via this link. this is the link-
https://dmp-portal.cic.gc.ca/enquiries-renseignements/case-cas-eng.aspx?mission=london
However, try sending email reducing the size of attachment to less than 3.5MB. make sure you type the correct email address, its advisable to copy and paste from website.
http://www.canadainternational.gc.ca/united_kingdom-royaume_uni/index.aspx?lang=eng