Endpoint Protection

I have a server where .tmp folders (directories) located in "C:\Program Files\Common Files\Symantec Shared\SymcData\sesmvirdef64" are continuing to grow...they are now taking up 14 GB of space.  SEP and SEPM are both installed on the D: drive and are version 11.0.2020.56

Can I just delete these folders?  If so, do I need to first stop any services to do so?  Is there anything else that I need to do?

Could this be related to the 2009-12-31 virus def update issue (https://www-secure.symantec.com/connect/forums/official-status-sepm-definitions-stay-31-12-2009-last-updated-04-jan-2010)?

Seems to be related to the issue you have mentioned.
Stop the symantec services and delete the temp files
I would suggest you to upgrade to latest version , as it fixes lot of issues.

Migrating to Symantec Endpoint Protection 11.0 RU5

http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2009090313483348 

I can't stop all Symantec services while the server is running.  What are the services that must be stopped in order for me to delete these folders?

Symantec Endpoint Protection Manager
Symantec Embedded Database.

https://www-secure.symantec.com/connect/articles/how-clear-corrupt-virus-definitions-sepm
Stop the Symantec Endpoint Protection Services:

1. Click the Start button and then click Run
2. Type services.msc and click OK
3. Right-click Symantec Management Client and click Stop.
4. Right-click Symantec Endpoint Protection and click Stop..

http://service1.symantec.com/support/ent-security.nsf/docid/2007123111551948

I was able to turn off services and delete the .tmp folders...thanks for everyone's help!