I have previously written about Lotus Protector for Mail Security integration with Lotus Notes 8.5.1 and later. Once you have it configured the client integration works really well, and had definitely helped me reduce the amount of mail in my inbox over the last couple of months.
I recently came across a situation where a particular client machine could not see the protector integration in their mail file. We checked the client version, notes.ini settings, mail template, and everything seemed correct. We launched IE and tried to use the web interface to Lotus Protector for Mail Security, and got this:
Other machines were working just fine (browser and Notes client), and that is when we can across this technote, which documents the requirement for TLS1.0 to be enabled in the browser in order to access Lotus Protector for Mail Security.
Sure enough a quick check of IE Settings showed that for some reason TLS 1.0 was disabled.
A simple check of the box, and Lotus Protector was accessible from the machine.
Technote 1444380: Web interface of Lotus Protector for Mail Security appliance cannot be accessed
As a reminder if you are using both Lotus Protector for Mail Security, and Lotus Connections, they don’t play nicely together in 8.5.1 or 8.5.2, this issue is not fixed until 8.5.3, in the meantime you can contact support for a hotfix.
followed an hour later by the correction: 
I wonder if these guys are just not smart enought to proofread their marketing campaigns before they hit send, or if this is a creative way to spam, either way they have earned a spot on my