My friend he has hotmail address but he is still not joined?

I am a moderator of my group... but all friend they have hotmail address and joined my groupe by link mygroup-subscribe@yahoogroups.com and them recieved e-mail and already reply confirmed to yahoo groups.. but i can't see them as a member and also they cannot recieve any mail from my group
My friend he has hotmail address but he is still not joined?
There have been some problems with hotmail addresses when it comes to joining Yahoo Groups. The Yahoo Groups technical team has been trying to fix the problem. They have asked that if the problem continues to please report it to them.