Review of previous postings:
John Rooks wrote in about Windows ME no longer making system restore
automatic checkpoints on his PC.  There was some discussion about what can
cause this. The main point is that system restore attempts to make a
checkpoint every 10 hours but only if it sees the system idle for 3
minutes, whatever "idle" means.  Programs that appear to system restore to
be keeping the system busy will prevent the automatic checkpoints from
occurring.

Mike M provided a lot of information and a lot of good advice.

I wrote that I had a similar problem, and that I had narrowed the potential
culprits down to:

Netpersec
TextBridge
AIM
Data LifeGuard Agent (Backweb)
Cm_camera
Rundll32 (possibly due to TweakUI)
InCD - Ahead's packet writer.  

The results from this weekend's testing:
I killed InCD and within a few minutes a system restore automatic
checkpoint occurred.

Since this software is for CD packet writing and this PC is never used for
packet writing, I have removed InCD.

However, this leaves a puzzle because the Automatic System Restore
Checkpoints quit in September 2006 and InCD was present and working on this
PC many months (probably years) prior to this.  Using Process Explorer
shows that InCD runs periodically (at least once every three minutes) but
uses much less CPU time than Process Explorer itself or many other
processes (explorer, vptray, etc.).

This prompts the question:  what is the definition (by Automatic System
Restore) of "idle" ?

At this point, I would guess that there was some interaction between InCD
and one of the other programs more recently installed (e.g. Cm_camera) that
is making it appear that the system is busy when it is not.