Non support on Apple Mail app on Shaw email system

Further to Mstuart37 question why Shaw email system has problems in linking with Apple iPads, I also experienced a similar case with my editor who lives in another city. Shaw is the internet provider for both of us, but my editor uses her iPad to receive and send her emails while I most often used my Shaw Webmail directly. It appears that this problem of the inconsistency in sending and receiving emails between us occur when there are attachments involved. If Shaw doesn't support the Apple mail app any more, then there is no other solution other than both of us using Shaw Webmail directly or to go to another internet provider. Very inconvenient. I now text her on her cell whenever I have to send stuff for editing to confirm that she has received them. There is nothing worse than sending out something important and getting no reply. This problem might resolve itself when Rogers take over Shaw and their Webmail system will no longer exist . This might be the reason why Shaw no longer supports any other mail apps other than their own. Hope this helps.