Ok!
I tried to have my little brain at work this few late days.
And I found this on your FAQ page:
http://www.romexsoftware.com/en-us/primo-cache/faq.html
Q: My boot partition is write protected, and I find that contents stored in level-2 storages always become invalid and useless after computer restarts.
A: PrimoCache implements a mechanism to check if cache contents stored in level-2 storages are synced with source disks. It traces and updates flags saved in Windows registry. However if boot partition is write protected, which means that these flags won't be updated, PrimoCache will think that level-2 cache contents are out of sync and reset contents.
Here is the important sentence:
It traces and updates flags saved in Windows registry.
I think that what is wrong is the use of cleaner/defagger registery tools.
I need your advice about this because I clean and defrag the registry every sunday since many years. My Windows XP32 was installed the 07/15/2007 for the last time. And before using PrimoCache I never had any problem, my PC run 24/7.
I think that I can clean the registry but have to stop to defrag...
What do you think about this?
