Laptop running Windows 8.1 running Norton 360 22.21.5.44, ran manual live update, returns no product updates required. 'New Version Check' returns have latest version. Windows 10 Desk Top updated 3 days ago to 22.21.6.51 OK although did not know that this version was available as no announcement issued (separate thread for lack of announcements). Tried to update Laptop today, ran manual Live Update 3 times + 'New Version Check', done reboot, still returns not required although MUI folder includes 22.21.6.51 folder along with 22.21.5.44 - any ideas ?
Anti-spam is active when Norton is active. What you are seeing is more than likely the AS definitions being updated. The lates version on my lappy is 20210806.048. At times, these definitions will miss a day, others they come once or twice in a day. Bjm's post is accurate regarding the latest Norton releases.
SA
~ at this time....users are 22.21.6.51 + Hotfix or 22.21.6.53
~ 22.21.6.53 = 22.21.6.51 + Hotfix
Norton Security 22.21.6.53 for Windows is now available!
1. What is the version number for this patch?
Norton Security 22.21.6.53
2. When will I receive the patch?
As is our standard practice, we are deploying the patch in a phased manner. We have released the patch to randomly selected customers, and will then monitor our telemetry, as well as this forum, for any problems or issues. Once we have confirmed the effectiveness of the patch, we will make it available to all customers. We will post an update on the Norton Community when we make the patch available to all customers.
3. How can I manually install these patches?
This patch is ONLY available via LiveUpdate, and is being released in a phased manner. You may need to run LiveUpdate and reboot a few times before your product is completely updated to the latest version.
4. What's new in Norton 22.21.6.53?
- Fix for an issue wherein product was crashing randomly - Thread
I just got it on my last 2 W10 systems so it is still being offered.
Jim 
Thanks for that - thought it was just me. Have latest update on DeskTop, working OK but noticed AntiSpam only runs once a day whereas used to be more than that - now appears to be running every 24 hours to the minute - sometimes coming up with failed Yesterday showed Saturday updated first on am boot, PM boot showed failed Sunday 6:55 am, did not show failed just prior to noon. Not certain about Insight maintenance, these are both showing as completed OK yesterday PM. Update - Insight maintenance has run - during first idle of day in 3 hours, anti-spam still at 4:48 pm yesterday. Licencing & product Maintenance ran 2ce today although these not to be in idle to run. Seems quite a number of postings on Community regarding various problems with 22.21.6.51 so perhaps it has been pulled - no official announcement.
I have the same problem on 2 of my W10 Pro systems. I did get it on my main system a short while ago. I assume it has been pulled.
Jim 
@mgirons I am also seeing the inability to see or get a product update on my machines, when doing a clean install of Norton Security. They all get 22.21.5.44 by default with the intitial install, no update to 22.21.6.51 offered after multple restarts and LU runs. My suspicion is the update to 22.21.6.51 has been pulled, due to having a "hotfix" released earlier this week to correct issues with that version. We Guru's will post back here for you if/when we have something we can report about what is actually happening. Thanks for being patient.
SA
Picked up latest version on Desktop on 26th when running manual LUDs, came as surprise as no announcement been issued. Ran thru' normal install procedure, up & running OK. Laptop last on during 25th but had no need to run manual LUD's. Yesterday intended to update laptop, ran manual check for updates, Product Updates showed not required, currently 22.21.5.44 installed. In MUI folder, both version numbers have sub-folders. Restarted, tried again, same result. Cold boot the same. Version checker returns up-to-date. Windows installed apps shows 22.21.5.44, likewise 'about'. Fast Start-up off, learnt that issue shortly after buying new 8.1 computer. Not the problem of installation but not recognising updated version out there. Very strange - laptop not in daily use, just use for back-ups & emergency computer.
Have you restarted your computer? Not Shutdown and startup if you have Windows Fast Startup feature enabled. If you use Windows 8/8.1 or 10, there can be an issue with the Windows Fast Startup feature.. See more information here.
FYI The New Version Check is always going to show up to date as long as your Norton Product is ver 22.x.x.x. It would only find a new version when Norton moves to 23.x.x.x