update primary SMTP

Hi ,

I wan to update around 500  primary smtp address of AD users  so that they will update office 365 portal.

My moto is if any users primary SMTP is different than what I wat to set then let script to update without changing other tab like windows ID ,UPN , login name  etc.

it would be great if can little trickly like group wise.

Don't forget to mark helpful or answer

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