Block labeled file from being uploaded to sensitive website

[Brandon_Tuck]

Hello, I'm trying to prevent sensitive files from being uploaded to dropbox.com. I have dropbox listed in the DLP Settings to be blocked, and I have the policy created, however, the file isn't being blocked when being uploaded to dropbox.

How can I fix this? Thank you!

[#2]

I found this one strange to get working! I block all domains for cloud upload then add some allowed ones but the rule under service domains seems the wrong way round to me. Try changing and seeing if it works. Also make sure you've populated your browse list with all the usual ones and if you're using Chrome make sure the Purview extension is installed.

[#3]

@Brandon_Tuck 

Assuming that you are using Purview Endpoint DLP to achieve this, you'll need to check the following:

1. Is the device that you are testing on onboarded in Purview Endpoint DLP
2. Are you using the Microsoft Edge browser? If you are using Chrome, you'll have to install the Endpoint DLP agent for Chrome
3. Check if the policy is set to block and is indeed live.

Alternatively, you can create a file policy but using Microsoft Defender for Cloud Apps. It will achieve the same outcome.