Since I added The PC Optimize, test pukes out at 37% of checking C..Tried all of the suggested tips.

Me too, for the first time ever, but mine always makes it to 99% on drive C. None of the tips worked for me.

Only thing I may have done is run some of the programs on Gibsons site grc.com and that may be causing a problem. (UPnP etc)

Browser Helper Objects Installed
Yahoo! Toolbar Helper
Adobe PDF Reader Link Helper
ContextHelper
TTB000000 Class
SSVHelper Class
Google Toolbar Helper
Google Toolbar Notifier BHO
Running Applications by Window Title
It is "normal" to have many strangely named windows on this list. Do not post questions about this information unless requested by the support staff.

AutoSuggest Drop-Down
TF_FloatingLangBar_WndTitle
CiceroUIWndFrame
SysFader
Start Menu
SysFader
Maximize to current monitor
AVG E-mail Scanner
Back
PC Pitstop Troubleshooting - Windows Internet Explorer provided by Yahoo!
MCI command handling window
Acrobat IEHelper
DDE Server Window
WOWExec
{A7E495BF-9589-4a6e-8479-DDA2D8D3C05F}
NVIDIA TwinView Window
QTPlayer Tray Icon
HiddenFaxWindow
gcasDtServHolder
GIANT AntiSpyware Data Service
DDE Server Window
{BE655EA0-84D2-11d4-9733-444553540001}
{44C6FB81-KBDWNDCLS-B4F7-11d4-9FDD-0800460222F0}
HelperMsgListenerWnd
HpqCameraDetectMonitor
HPWU
HP Photosmart Printer Series
HPSYSDRV
Sunkist.NOTIFYICONDATA.hWnd
Connections Tray
Power Meter
MS_WebcheckMonitor
NVSVCPMMWindowClass
AVGEMC
AVG Free Edition - Control Center
GDI+ Window
Program Manager
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