If you are getting a 403 error while using the DESelect application, it is most likely something in the browser is blocking the DESelect cookie from being used.
1) Please check for the following:
a) Are any Chrome extensions active that might be blocking the cookie? Deactivate the extension and go to step 2.
b) In Chrome, go to Settings > Privacy and Security and make sure that:
- Allow sites to save and read cookie data (recommend) is enabled
- Block third-party cookies is NOT enabled.
- Under section Block, there is nothing related to DESelect.
In other browsers, similar settings need to be checked.
2) Logout of SFMC, clear cookies for DESelect on the users' computer, and relogin to SFMC and DESelect.