Some anomalous files under Norton eating up HDD space

A few hours ago Windows suddenly gave me a popup saying my C drive is running low on HDD space, I checked my drives and my C drive had 1.72MB left!

 

So I poked around and used an old program I had, WinDirStat (it's great btw, gives you a visual idea of where your space went) and noticed a large chunk of anomalous files. 18GB of it.

 

Folder:

C:\ProgramData\Norton\{0C55C096-0F1D-4F28-AAA2-885EF591126E7}\NAV_18.1.0.37\CmnClnt\ccSubSDK\

 

Contains 9998 files with names {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxxx}, where x = (0-9, A-F) and a single submissions.idx file

 

File size ranges from 16 bytes to 4.6 MB

 

My system is running Windows 7 Ultimate x64, Intel Core2 quad Q9550, Norton AntiVirus 18.5.0.125

 

 

Are these supposed to be there? Are they safe to remove?

Thanks in advanced