red circle - program shutdown

[intanet]

Hey,
Got the red circle on the Avast ball icon again which means the program is not operating.  First time it happened, I clicked the link on the popup that comes when you click the Avast icon in the system tray which brings you to the help site where it tells you which services need to be running in order for avast to work and I noticed that 2 of those services had been stopped.  I did not stop them and it is still is a mystery how that happened but anyhow, I started the services and Avast was working again. Some one suggested in a post that I remove any trace of Norton (my old anti virus program) which I did and every thing was fine...until last night when I booted up and the little red circle was there again.  Thing is, this time all the services were running so why did this happen?  The other suggestion was that the Service : "Remote Proceedure Call" might need to be updated so I went to Windows Update but there was no update for me.  I have the newest version.  I had to download and reinstall Avast and now it is working fine but under the exact same computer conditions as before when it didn't work?  Any ideas? 
Thanks for your help,
Angie
I checked out the help file, message board and also the "other Questions" but could not find anything.
P.S. Just for the record, I rebooted twice, but it didn't work.  I then uninstalled and rebooted and then I installed the download and rebooted and so far it is working.

[Eddy]

Is there any error message in Avast's log file?
Is there any error message (security related) in XP's log files?

[Lisandro]

RPC error is generally related to other antivirus present or, at least, firewall blocking. RPC error may also be because of avast! services being stopped. Anyway, RPC error is most likely correct by this procedure:

Go to Control Panel > Add/Remove programs > avast! antivirus > Remove
Then choose Repair function in the pop up window (Repair).
If this does not help, can you uninstall / boot / install / boot again?

Also, take a look into Administrative Tools > Services and see how the four avast services are set to start (automatically or manual).

[intanet]

I uninstalled Avast and then I reinstalled it again so the log file for the first Avast install isn't there anymore.  How do I find the Windows log file?
All four avast services are set to automatic.  Right now the reinstall is working fine but if this happens again, I'll run the repair. Thanks for that info.