Gee - it wouldn't surprise me if this was indeed another error

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I have the same problem here, where I am temping - have been here for some 4 months now and like you, the only way I often see something that I need to deal with when a group email has been sent out is because I have access to my boss' emails.
His PA, who is on leave, is on the group list and my name is also supposed to appear while I am covering for her but despite countless times of asking various people (by my boss as well as me), it has not been added.
During a telephone conversation with one PA who needs to add me to her particular list, I mentioned it as a gentle reminder and she admitted it was one item way down on her 'to do' list and that she would get to it at some point yet another PA did add me while I was on the phone to her - depends when you catch people I suppose.
Doesn't help that such lists are not 'central' (well, not here anyway) and several people need to be involved.
To be honest, I've given up now. Since I can see emails on via the boss' in-box, I just pick things up from there. Maybe this is because I know this job won't last forever but if I was permanent as you are, I would like my name updated.
Not sure how you can ensure individuals update their lists - short of trundling over to their office and standing over them while they do it - along with a menancing look on your face

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I often find that things get done after speaking to someone rather than sending a request in an email - it seems the personal touch often helps.
Good luck
