USB Mass Storage Devices Not Recognized

I have been encountering problems with Windows XP recognizing new mass
storage devices on my system. I inserted a SanDisk U3 Micro 8GB with Ready
Boost, and the system indicated it was being recognized except for the lack
of the U3 logo in the lower right hand corner of the task bar. When I tried
to add or delete files in My Computer, the system stated the following;
"Cannot delete file: Cannot read from the source file or disk." According
to SanDisk, it is supposed to show a new CD drive as well as a new hard
drive. Why U3 does this I don't know as it makes a simple procedure more
complicated than I like, and seems totally unnecessary as all I want to do is
to transfer files from once computer to another. I have another Mass Storage
Device that is a Centon DataStick 4GB that initially I was able to create
folders on for the possibility of loading various documents, music, and
photos etc. However, it would not allow me to load anything into the
folders, and when I tried to delete one of the folders, it stated that the
disk was write protected. This same problem was encountered with the Staples
Relay 4GB as well, when it would stay connected long enough for me to access.
Usually it would go off line after a few minutes, and all lights would go
out. I was able to (supposedly) format both of the above last two drives,
however now My Computer indicates that any of the mass storage devices have
NO FREE SPACE available! Also, on the Centon DataStick I found corrupted
files inside some of the folders which I did not put there as I have been
unable to install anything into these folders! Does anyone have any ideas
about how I can correct the recognition problem that exists between the I/O
USB system/OS and the removable storage device? How do I permanently remove
the write protection that has been installed on some of my files in My
Documents as well as the removable drives? This seems to be the underlying
cause of everything, and I have tried my best to remove the "Hidden," "Read
Only," or "Archive" from the file attributes to no avail! It always comes
back as Read Only or Hidden, or Archive or all of the above.