Why are none of my System Restore points working?

I have tried the last seven or so Restore points that show on the calendar, which go back to Friday. Every time I have gotten : "Restore Incomplete. Your computer cannot be restored to [date]. No changes have been made to your computer."

I did have the System restore set at My Computer > Properties to only save 6GB. I don't see why that should have kept me from having the last several days. (Now I have put it back to Maximum.)

What can I do to get it to start saving points for me? Something like this happened last time I tried to use it.



Windows XP
Home Edition
Version 2002
32-bit
Service Pack 3

Dell DIMENSION DIM2400
Intel(R)
Pentium(R) 4 CPU 2.66GHz
x86 Family 15 Model 2 Stepping 9
2.05 GB of RAM
Graphics Card: Intel(R) 82845G/GL/GE/PE/GV
Graphics Controller, 64 Mb
Hard Drive Size 114.4GB
Free Space was 35.8GB; now 22.0GB because after backing up My Documents on Google Drive, Google Drive has duplicated the whole darn thing on my hard drive
Motherboard: Dell Computer Corp., 0G1548
Antivirus : Webroot Internet Security

 

I did use CCleaner Sunday night, but I did not use Drive Wiprer. I also used Advanced Uninstaller Pro's temporary files and cookie cleaners, ATF Cleaner, Wise Care System Slimming, Ashampoo WinOptimizer Driver Cleaner, Advanced System Care Pro Iobit Disk Cleaner, and Kingsoft PC Doctor Junk Cleaner. On none of these did I leave all settings checked; rather I scrutinized them carefully. (By the way, all of them except ATF Cleaner reoved a meaningful amount from my hard drive.)

 

OK, I did it in Safe Mode and was able to get a System Restore done.