Hi @Brian538
Welcome to our forum!
I mean like if Microsoft sends you a SMS after account closes, do they keep those texts?
If you close your Microsoft account, you have 60 days from that closure to sign in and reopen it. After that 60 days, your account and data expire. You can’t use your old account name to create a new account after the account-deletion wait period expires. More information, see: How to close your Microsoft account - Microsoft Support.
And do they send an email to an alternate email address when you sign up and with what do they use to send it. Do they save these as well?
Yes, if you use email to verify your account. The Microsoft account team will send you an email to verify that your account has the correct address to keep your account secure.
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