Electronic certificates on iOS mobiles

iOS Error when importing a .cer copy

.cer copies can be imported into IOS, although this should be avoided if possible. They are not valid certificates and do not appear in the signing window if you try to use them (resulting in a 403 error).

Importing a .cer copy will not result in any error message, so the invalid copy will remain installed. If you go to "Settings", "General", "Profiles", the electronic certificate will appear in the list of certificates and will not be distinguished from another imported and correct copy with a .pfx extension.

If you look at the details of both certificates they will also appear to be the same, however a .cer never appears in the list of certificates available to use. If you only have the certificate with the .cer extension in the certificate list, a 403 error appears directly.