A day or two ago I attempted installing Avast's new version 5.
The program itself required updating, as did the virus database. I opened my Comodo firewall to give both the app, and it's updater permission to access the Internet. After waiting around 10 minutes for both, with no progress on either, I closed the app, reopened it and tried again. With a similar lack of action.
At this point I decided to go back to version 4.8, and the repercussions are still being felt.
I was successful in reinstalling version 4.8. But after that, for reasons I can't guess at, Comodo went nuts. It gave repeated warnings about what Malwarebytes Anti Malware was trying to do, and had to be repeatedly told this was a trusted application, it has been installed for a year or more, ever since AVG discontinued their stand alone Anti Spyware app. Now mbam is working properly in most respects, but is denied access to notepad so it cannot generate reports on scans.
And one other application, dB Poweramp Music Converter is playing up, it will no longer attach cover art to music files as a batch, I now have to add the cover art to each track individually.
In another post, on another thread at DAL I was initially denied access to the extra Smilies.
I also get Java access denied warnings when I start Firefox, which does start anyway.
What the hell happened? Do I need to start submitting HJT reports? Or should I try going back a few days using ERUNT? I like that option.

Problem seems to be solved.
ERUNT did the trick. A truly nifty little app.
Get it here ERUNT and NTREGOPT