you need to re-register the liveudate..please followe these steps it should fix the issue.

LiveUpdate and content troubleshooting for the Symantec Endpoint Protection Manager

http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2008091613592648

1. From the Start menu select Run
2. Enter the following command including the quotes:

   "C:\Program Files\Symantec\Symantec Endpoint Protection Manager\bin\LuCatalog.exe" -cleanup

   This command will unregister all Symantec Endpoint Protection Manager content from LiveUpdate. We will then proceed to re-register the content again with LiveUpdate.

    

3. From the Start menu select Run
4. Enter the following command including the quotes:

   "C:\Program Files\Symantec\Symantec Endpoint Protection Manager\bin\LuCatalog.exe" -update

 Rafeeq, that did not work.

Please follow these steps and then register the liveudpat. should fix the issue.

https://www-secure.symantec.com/connect/articles/how-clear-corrupt-virus-definitions-sepm

 I think something else is wrong because I've done that as well and every time I run LU, it says the Scan Engine Win32/64 11.0 is up to date but it's not. Unless of course the last time it was updated is 8/20/2008 which I find very hard to believe.

I checked the LU settings for the server and this is what it lists for "Content Types to Download"

I don't see an option to update the PTP scan engine. Is that part of the "Client updates" option?

Run a repair for SEPM and then try

Repair did not work either.

I also noticed after running LU in the console that "Intrusion Prevention signatures Win32 11.0 failed to update."

The link will tell you how to stop the service.  Edit the registry and then delete files that may be corrupt, causing this problem.
It is easy to follow.
I will tell you that we ALSO had to un install windows defender to make this all happen.  We weren't even using it, but somehow it helped us work on this update issue.

http://service1.symantec.com/support/ent-security.nsf/854fa02b4f5013678825731a007d06af/691fb01f62f2a700882573c2006d6de7?OpenDocument

A couple things got updated after doing that but the issue still remains that the scan engine is still dated 8-20-2008.
 

We're running RU5 and we have the same TS/PTP scan engine;
Win32/64 11.0  2008-8-20 rev. 001

 Back to the top...

I built a new SEPM server and a new database and clients are still not updating.

I would like to use PTP since we paid for this whole package but I can't push out software that doesn't update correctly.

Rebuild the content folder 

Stop SEPm and SEPM database service
Take a backup and delete everything inside

HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\Symantec Endpoint Protection\Content

and 
\Program Files\Symantec\Symantec Endpoint Protection Manager\Inetpub\content

then start both the services.

 I've actually done that as well without success. It was in one of the tech articles I found.

I just tested something that surprisingly worked.

I changed the LiveUpdate content policy to "Select a revision" for "TruScan proactive threat scan commercial application list" which lists the latest revision as 12-04-2009 rev. 018 and set the primary LiveUpdate policy to pull updates from the Symantec internet site instead of a GUP. Now PTP is showing the latest defs. I reset the option in the content policy to "Use latest available" to see if starts pulling updates correctly in the future...I'll be keeping my eye on it.