The release of 12.1 RU2 also included an updated CleanWipe utility & now it works/performs much better.
Supported Operating Systems
Windows 2000 SP4+ (requires MS KB816542 included in Update Rollout 1 for SP4)
XP / Server 2003 / 2003R2
Vista / Server 2008
Windows 7 / Server 2008R2
Windows 8 / 2012 Server
Both 32 and 64bit versions, where applicable
Prior to run Cleanwipe you can download Symantec Diagnostic Support Tool to identify a problem.
CleanWipe tool should be used as a the final solution for removal of the product.
It's a Zip file with password protected. Need to extract Zip file prior to run Cleanwipe.exe
Now let's see how it works.
This is the welcome screen, click on 'Next'
Accept the 'license Agreement'
This is the major change if we compared with the last Cleanwipe version.
Now We have an options to choose required options only.
Reboot is mandatory to remove any of the above product however now you can hold the reboot by doing unchcek "Reboot Automatically".
This utility doesn't required multiple reboots if we compared with previous cleanwipe tools.
To receive this tool you need to contact Symantec Support.
Support Support - http://www.symantec.com/support/contact_techsupp_static.jsp
Check this article for more details.
I hope it's informative.