Looking on the internet deeply has found these results:

at email is the most popular phrase on the web.

in email 10 results on the web	at email 11,400,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
There's no tone in email. You will find this has become quite common in email marketing but should be used in other formats as well... Especially in email marketing, when all of your contacts should be clean and want to receive your emails. CPM is widely used in email marketing and banner advertising too. Compacting the PST file also results in email deletion Please supply the pictures of the broken items in email. Sends the records embedded in email as HTML instead of a record file in the attachment. Specifically, he said, the notes showed up in email.	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

in email

10 results on the web

at email

11,400,000 results on the web

More popular!

There's no tone in email.
You will find this has become quite common in email marketing but should be used in other formats as well...
Especially in email marketing, when all of your contacts should be clean and want to receive your emails.
CPM is widely used in email marketing and banner advertising too.
Compacting the PST file also results in email deletion
Please supply the pictures of the broken items in email.
Sends the records embedded in email as HTML instead of a record file in the attachment.
Specifically, he said, the notes showed up in email.

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.