No. Email addresses are not case sensitive. Having letters in all lowercase makes the email address easier to read, but the oversight won't stop your messages from being delivered.

Are emails case sensitive outlook?

Email addresses have no case sensitivity. This means that even if you registered your email address in all caps or alternating caps, they will still be regarded as long as the characters are matching.

Does punctuation matter in email addresses?

Adding dots doesn't change your address, so dots aren't why you got someone else's mail. Instead, the sender probably mistyped or forgot the correct address. For example, if someone meant to email but typed , the message went to you because you own .