Why did my friend's email combine with another one in my inbox?

[mech-eng]

hi, all. there was mail sent to me in my hotmail account. after a friend sent me an email from his
gmail account. but it is a strange case that his email is combined with that email. it should be there
as an abstract email but it combined with another one. what is the problem.mail with no profile picture is friend's mail
before it was another mail.they combined.

 

[adjacent]

I don't understand what said.Can you be a little more clear please. :)

 

[mech-eng]

I don't understand what said.Can you be a little more clear please. :)

there was a mail on my coming box, and then a friend sent another mail.that mail combined with
another mail in my mail box the picture is the situation.mail with black remark is friend's mail and mail with
red mark is another mail in box before it sent. when I click I see that they are combined like the situation when
we answer a mail the two mail become combined.

 

[Routaran]

i just checked my hotmail account and information is not displayed like that. I'm guessing that the emails are being organized in a thread like fashion, like a forum so that it's easier to follow a conversation that occurred over email. This may be a setting that needs to be changed.

Is the subject line on all the emails the same or has "Re:" in the front? That's how mail programs generally figure out how to group messages.