What is the best way to stop people from sending emails to the wrong external person ?

[smithal]

Hello, 

What is the best way to drive the right behaviors in order to reduce the risk of sending sensitive information to the wrong external parties ? 

What we have done to date..

1. Educate users:  about Auto-compete and how to clear the nickname cache

2. Enable Mailtips for notifying people they are sending to external parties  

We are considering the following counter measures to further reduce the risk of people sending to the wrong external parties. 

1. Add a prompt before sending emails (/w VBScript)

2. Client side rule to delay send 

3. Investigating 3rd Party solution - Any recommendations ? SendGuard, Anitidote who is good in this space 

Longer Term 

Investigate DLP policies on Exchange as we prepare to move to EXO (Exchange Online) 

[#2]

@smithal I would recommend Egress desktop as well as Tessian, both a good products to prevent this happening. 

I have also seen custom Outlook add-ins used, but they tend to be unreliable, and users just ignore them after a while because they are annoying. If mailtips are not enough, have a look at the products above.

[#3]

@CloudHal

Thank you I'll take a look..