0x80040d03

good afternoon,
I have a problem with outlook:
it stops dead. This happens erratically, and often.
I can see that this seems to be a windows search service error
The registry value cannot be read because the configuration is
invalid.Recreate the content index configuration by removing the content
index (0x80040d03)

Now it should be simple, except that I have no idea what file should be
removed, just to be born again in proper shape...
How can I reach it?
Even if it is not the fundamental cause of my problem, I would like to
correct it.
thank you
Robert hirschel