Nah, This is not the problem, my CheckCommandLine does this :
Divide the command entered (with a left/right, as I know the number of letters possible), then if the first part is A, check the second part. Then do an OpenForm A with the second part as argument. I use this in my OpenArgs in my form_open. Or at least, it should work (I'm still coding).
But I'm wondering how I can send an icon by mail. I have a function which creates a mail and send it to a number of people. For instance, as an hyperlink seems impossible, I want that when someone click on button B in form A on the 1000th record, Access creates an icon with the command parameter in it (like /cmd A_1000), then attach it to the mail which will be sent using the function above, so that when they reecive it, they just have to click on the icon to open access on form A, 1000th record.