Zillah, you're one of countless folks that have discovered how Avast can ruin your day by refusing you access to all other parts of your systems, if you don't rein it in. Avast certainly acted for me (at first) as it has for you. I disabled all of the automated 'help' it dropped into the PC, as it assumes everything is an attack. The first reboot, Avast claimed my MBR was corrupted; I had to boot to safe mode, Revo (uninstall) Avast, then research the online forums and complaints describing what Avast users have experienced; YMMV.
Avast has a decent A/V engine, as long as you don't let it rule your existence. There have been instances in the past, when an update has borked people's machines, but that is something that happens to most people who depend on AIO security systems, when they don't understand how to control the package. I quickly disabled all restrictions in the package. If you learn the details, and can fine-tune Avast to your liking, then whatever you want to devote to it, especially if you didn't opt for the free version, you'll get out of it what you paid for it. This is directly related to your network, type of internet connection, if you use a VPN, and of course, your level of online paranoia. I use the free package on Win7x64 Ultimate, for the A/V.
Best advice, disable everything except anti-virus, set it to scan downloads, then begin to learn if you want to use the rest of the package. Do scan your entire system manually, as needed, including your boot sector. If you Avast loose with it's automatic modes, it will drive you batty telling you something or someone is either a threat or attacking you. It's tough to tame. Set the A/V to manually update your -definitions-only- perhaps once a day or week as and when you feel is right for you. You don't have to update the program engine as much as it recommends, just the definitions. Whatever you do and/or change, be sure to write it down; if you forget a setting, you'll wonder why something suddenly stops working, and it's usually Avast trying to do what it thinks best. When Avast thinks its found a dangerous bug, you'll need to look it up on VirusTotal to be sure, otherwise you'll be minus a file, either sent to the quarantine box, (or worse, deleted), when it may well be harmless. Avast can be, shall we say, overly generous with the number of false postives it generates.
Hopefully, you maintain a properly managed firewall either in your router, or a seperate PfSense router/firewall. If you are lucky enough to have a good router with firewall built-in and/or a PfSense firewall build, a personal software firewall on your Win7 computer is highly desireable, and recommended. If you know your stuff, you can almost eliminate all of the 'phone-home' helpfulness of Win and other programs. I built thousands of windows desktops and gaming systems before I retired, and as a personall preference, never cared for the Windows A/V or firewall, since it automatically allows Windows to do whatever MS has preordained and wants -your computer- to do for them (phone-home). Other folks actually prefer the Win A/V-FW, again, YMMV. There are good free firewalls that will work well and are much easier for the majority of home users to configure (and comprehend), especially if you aren't a network wizard. I hope this helps, Cheers.
