You should be okay here. Bona fide, a reading by WinPatrol.
If not, in situations like this, one of the members who is more knowing of WinPatrol - like YoKenny - would add to the thread.
I think the changes that you have made are good, despite that the problem is not yet resolved, you have enhanced yr software platform.
This issue which you have (thankfully) brought to attention is not exclusive to avast as you can see from the following link -
http://mcafee-ext.hosted.jivesoftware.com/thread/21005?tstart=-1Nor exclusive to security programs -
http://forums.adobe.com/message/2901913?tstart=0What I suggest may be the issue - insecure installation of the application to the 64bit architecture for one reason or another, but evidently the application faulting as the outcome. Whether this will prevent the application from performing in runtime is another thing, and it may in fact run as per normal even though the error message is generated and the app may close at Startup. (which may explain why yr avast might continue to update as per norm, although seems it wont right now). Regardless, as DavidR has pointed out, it appears the issue is one for the devs to deal with - whether writers of the app or Microsoft itself (which seems more likely).
The problem here is that although you may be able to work on despite this issue or perhaps craft a workaround, there is a possibility that the insecure install lays open a vulnerability in the internet explorer platform, and this vulnerability may be exploited by malware. That said, I am not sure what is yr best course of action, and granted I am only speculating about the situation you are experiencing. Unfortunately I cannot replicate the situation, as much as I would like to.
There is also the possibility that one of yr other third party programs is causing this error situation and it is not an issue with 64bit architecture. However, I would not like to speculate further than I already have, and suggest you could possibly take the matter up with Microsoft support.