Standard shield does not install

I used Avast’s uninstall utility, ran in safe mode, downloaded fresh version, installed and yet the on access does not work (ball with red circle). I cannot start avast on avast because a dependency - standard shield - is not available. It also shows the RPC dependency, but RPC is always active for windows, so that doesn’t make sense. I’m frustrated and about to try another anti-virus program unless this gets fixed.
WinXP-SP3; Intel 1.7GHz; Sony Vaio VGN-S360P;IE7.0

Hi bogeymaker!

There are more possibilitys of what could be wrong on your PC. So some more information would be helpfull.

Do or did you use any other Antivirus?
If yes, which one and how did you remove it?

Which other security software is installed on your PC? (Firewall, Antispyware,…)

yours
onlysomeone

Can you try to repair your installation?
Go to Control Panel > Add/Remove programs > avast! antivirus > Remove. Then choose Repair function in the popup window (Repair).

If this does not help, can you uninstall / boot / install / boot again?

Do you have any other antivirus installed in your computer?
Did you have in the past? Which one?
Do you use a firewall? Which one?

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

One of the most common causes of this Red circle with bar over the avast ‘a’ icon is another AV installed or remnants of one remaining, the purpose of onlysomeone’s question.

So answers to his question may help us to help you further.