Program cannot activate resident part

I have a problem with something nobbling Avast.

I install it, all works fine for a few days then Windows tell me Avast is no longer running.

I tried to reactivate it but I get Program cannot activate resident part (Standard shield provider not found)

This has happened three times now

Each time I un-install and re install and all is fine for a few days.

A repair fails to work , it has to be an uninstall.

I have no other security software on the system , this was a clean install.

It looks to me like some kind of malware in deliberately nobbling Avast so that the system is then vulnerable to future attack.

I am beginning to wonder if Avast can be trusted any more with my safety.

Advice would be greatly appreciated.

I am running Win 7 32 bit

Can you schedule a boot-time scanning?
Start avast! > Right click the skin > Schedule a boot-time scanning.
Select for scanning archives.
Boot.
If infected files are found, it’s safer to send them to Chest instead of deleting them.
This way you can further analysis them.

Also, I suggest a full computer on-line scanning:
BitDefender
ESET NOD32
F-Secure

After that, I mean, if your computer is really clean, I suggest an avast installation from the scratch.
Just to be sure, hasn’t any antivirus being installed before avast?

As I said, I have done an avast installation from scratch THREE times now

and NO, no antivirus was installed prior to installing Avast.

I don’t know whether this is relevant but if I start Avast and click the button to look in the chest
I get an error that: “the RPC server was too busy to complete this operation”

Also if I click on the disabled Avast blue ball in the system tray I get a popup message:

“The AAVM subsystem detected an RPC error. The operation could not be completed.”

This error is generally due to another antivirus or security program installed. So my insistence on asking you. Sorry.
Maybe Microsoft Security Essentials? ???
Sorry I do not use Windows 7 (yet).

I think I may have solved this.

I opened the Services window by right clicking on Computer and selecting Manage from the popup menu

I opened Services & Applications and then Services

There is an entry called “Remote Procedure Call (RPC) Locator”

It was set to Manual and the details said:
In Windows 2003 and earlier versions of Windows, the Remote Procedure Call (RPC) Locator service manages the RPC name service database.
In Windows Vista and later versions of Windows, this service does not provide any functionality and is present for application compatibility.

I right clicked on the name in the list and selected Properties, I changed the startup type from “Manual” to “Automatic”

After a reboot my Avast was working ok again.

Good find!
Merry Christmas.