Here's where I'm at now.
When I couldn't even do a manual update, I did some further checking and found out that my Windows Defender had not successfully updated for some time again. Back when I had that happen before, Microsoft had suggested that I go into MSCONFIG, disable all NON-Microsoft services, and disable all startup items. Then I was able to successfully update Windows Defender. I then went back and enabled everything that I had disabled.
I decided to try this again, only this time I ONLY disabled all the NON-Microsoft services and left the startup items alone. Once more, was able to update my Windows Defender. While I was at it, I tried doing a manual update on Avast, but nothing seemed to happen. I went back to MSCONFIG and enabled the Avast items I found and was then able to do a manual update of both the iAVS and program.
This morning when I turned on the computer, I had my fingers crossed. I was amazed/surprised when the box popped up a a voice told me that my "virus database has been updated"!!
That leaves me with 5 services still disabled, with one of those possibly causing all the problems?? The services still in question are:
1. Ati External Event Utility
2. Google Updater Service
3. iolo DMV Service
4. Symantec Core LC - I did have this one disabled before and had the problems, so it's probably not this one.
5. XAudioService
Unless anyone has some ideas, I will slowly enable these services one by one and see when the problems recur. Then I'll have to try to figure out if there are updates available for the offending files.
Does this sound like a reasonable plan?? Thanks for your help so far.
Steve