When a User tries to click the link in the notification email for quarantine message, they are getting the following error:

"The link or email address is invalid or the token has expired."

The link to collect the quarantined email is encoded with Office365 SafeLinks.

The original URL to retrieve the quarantined message is encoded and decoded with Office365 SafeLinks incorrectly.

If you use the URL before it is encoded with Office365 SafeLinks, the link should work correctly and email should be released from quarantine.

To decode the already encoded URL, please visit Office365's own Decoder at the following link:

Office 365 Advanced Threat Protection Safe Links - Link Decoder

You can then use the decoded URL and paste it in a web browser to release the email from quarantine.