OK, after several hours of being frustrated with this same problem I finally
figured out what to do.
First, open up Disk Management (control Panel>System and
Maintenance>Administrative Tools> Create and format hard disk partitions)
Now, if your disk manager looks anything like mine, there will be 4 or 5
disks showing, one of which is called "NVCACHE." The NVCACHE is the "cache
that already exists on the system." You must delete this disk in order to
enable ReadyBoost on your other device.
To delete it you may have to assign it a letter (right click NVCAHCE>change
drive letter and name) Just give it any letter that isn't already in use.
Click OK. You will notice that If you look under Computer the NVCACHE drive
is now visible but it will not allow you to delete it from there. You must
delete it from the disk manager. To do that simply right click NVCACHE from
the Disk Manager and choose "delete volume" a confirmation/warning message
will pop up, just click OK. (Note: you may have to have Administrative Rights
to delete the volume, I'm not too sure because I was signed in as
Administrator when I tried this.)
You should now be able to pop in your USB Drive, SD card, or whatever and
enjoy the benefits of ReadyBoost.
I hope this works out for you as well as it did for me, Good Luck.
I just have to say that I've looked all over the internet for a solution to
this problem even contacted Microsoft support for an answer which they could
not provide me with, and I think it's kind of funny that I, a 16 year old
kid, figured this out when no one else could.
Sorry, just kind of a pride thing.