Hi,
"Dear Mr.Heninkton,
Could you be so kind as to paste a web links into your webportal in all the next letters.
It will help to save a lot of time and it's more comfortable. "
"Dear Mr.Heninkton,
I would be grateful if you could paste a web link to your webportal into all future emails.
It will help to save a lot of time and be much more convenient.
Clive