How to deal with arrogant e-mail of a student
How to deal with this?


Dear [student],

Thank you for pointing this out. 

[1 or 2 more sentences of explanation]

Sincerely, [your name].


  What troubles me is the attitude, which I found it kind of offensive (but I might be wrong).


Maybe the email is offensive, or maybe the student just wrote an email from their phone. Maybe they are actively trying to be a jerk, or maybe they just don't know how to behave properly. Maybe they are just trying to be a troll. In all those cases, I have found the best way is just to not engage and write a neutral response that does not comment on the perceived rudeness.


If it's just a regular student writing an email from the phone, this does not create a conflict out of thin air.
If it's a jerk or troll, this does little to satisfy their hunger for drama.
If it's a student without manners, well, you are not their parent - don't make it your job to educate them on proper email etiquette.


What I certainly would not recommend is "inviting" them into your office for some sort of explanation, just for writing a factually correct but unfriendly email. You are, again, at worst creating a conflict where there is none, and at best spending significant energy trying to educate a fellow adult on basics of etiquette.


  But I feel that the student would create same issues in case some typo is found in the subsequent notes and make similar comments.


So what? If they have a real concern, address them. If they make things up to feel important, either ignore the email or tell them that you do not see the issue.