Many ISP email servers block sending when you are out of their network. SOME ISPs have special settings to allow sending when out of the network.
Since you didn't reveal the email server, ISP or such all I can write is it's true.
Bob
Hello,
I recently purchased a Samsung S5. I set up my email with my service provider and all incoming and outgoing servers and settings are correct.
I am able to receive emails when i am out of wifi through my data plan but for some reason i can not send emails using data. My emails are held until i enter a wifi network.
Please advise

Chowhound
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