Vista - Content Index service was Stopped

I don't look at my system or app logs every day. But when I checked them
recently, I found that my application log is full of this error:

"Advise Status Change failed. The system is probably low on resources. Free
up resources and restart the service.
Context: Windows Application, SystemIndex Catalog

Details:
The content index service was stopped. (0x80041812)"

Every 7-10 seconds, the app log shows this error, categorized as:

Level: Error
Source: Search
Event ID: 3026
Category: Gatherer

I ran "perfmon /report" and the report is squeaky clean - no errors reported
and system resource utilization is low. Low CPU utilization, low pagefile
use, lots of free RAM, very low disk I/O, etc. I disabled all indexer
catalogs, and I've rebooted multiple times.

Unless I disable the Windows Search service, the error fills the event log
to such an extent that the log contains no other data. One interesting
point is that, although the details state "The content index service was
stopped. (0x80041812)," the service is actually running. When I manually
stop Windows Search, I get Event ID 1013: Windows Search Service stopped
normally.

Does anyone have ideas on this problem?

--Dave