Vista - Vista "History" won't open or is corrupted

I have had a problem for a few weeks on a Vista SP2 box that I never had
with Windows before. When I try to open up Vista "History" reached @ ctrl+H
and arranged by days, it stopped opening a few weeks ago. I have looked
long and hard for ways to fix this and I've come up empty.

I've tried SFC /scannow many times. I've tried to use Startup Repair which
in my hands will fix a number of significant componetns of Vista that are
broken when nothing else will to no avail. No system restore point would
fix it when it first happened. Running the bcdedit command line switches
often helps me fix a badly broken or a badly broken no boot vista quickly,
but it won't fix this problem for me.

I'd appreciate any help in fixing what seems to be a corrupted Vista SP2
History. Plenty of people have the public Beta of Vista SP2, and they don't
have problems with history, so I doubt it's native to SP2.

TIA,

CH