3 ms·

Most often a Google Apps email address.

• amelius 10y ago
  Lots of companies prohibit the use of gmail. Even sending to gmail addresses is sometimes prohibited.
  • gkya 10y ago
    > Even sending to gmail addresses is sometimes prohibited. How do you know it's not a Google hosted email address if they use a custom domain (with a Google Apps plan one can use a custom domain on top of Gmail)?
    • smrq 10y ago
      Nobody's saying that arbitrary corporate restrictions are well thought out.
    • captn3m0 10y ago
      You can sniff MX records fairly easily to figure it out: https://github.com/jace/mxsniff https://github.com/jace/mxsniff