Does she have voice service in Europe? Since she is outside of her "home" area, access to voicemail is by dialing her own #, and pressing # when her greeting starts to play, rather than using *86. And this will work only if she has international calling on her 4S.
Alternatively, she can call her own # from any phone (and it will cost whatever the international calling rate is) and press the # key when her greeting plays. She will likely need to dial the code for US calls first, then her cell #.
Europe sounds great to me! Since your daughter is out of the country
she can call her own voicemail from any phone including her wireless phone. She would call her number. Once the message starts press the # key. As SusyQ stated she will need to dial the code for US calls first, to complete the call. I hope this helps.
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