Avast hangs

I downloaded avast7, when I use it in the through mode only it runs for a while and then hangs at different points.
If I run it in standard mode it seems to run fine. Is this standard mode enough security to pick up any viruses?

The short answer is Yes IMHO, a thorough scan could be digging very deep, extracting lots of data in a large .cab, .iso, .zip, etc. so it may take some time to both extract and scan. But, it shouldn’t do that for long periods, you don’t mention how long it hangs for (?) or what your system performance/resources are.

Archive (zip, etc.) files are by their nature are inert, you need to extract the files and then you have to run them to be a threat. Long before that happens avast’s Standard Shield should have scanned them and before an executable is run that is scanned. Thorough is also by its design very thorough and perhaps a little overkill for routine use, were a Standard scan without archives should be adequate.

I have only ever done a through scan with archives once shortly after installation just to ensure a clean start state, but with XP for example avast will do a boot-time scan after installation if you select it, this I believe will be quicker and reasonably effective. Like everything in life things are a compromise.

How exactly does it “hang”? Is it just the scanner, or the whole computer? Can you start Task Manager? Does the mouse cursor move?

Just avast hangs,I can access taskmanager, but it’s very slow. The little bar at the bottom of the avast screen keeps going back and forth.Yes, the mouse moves, (especially when my cat comes in the room)lol.
But if the standard scan is sufficent, then I’ll be happy with that, as I really like avast.
It picked up 2 trojans that bitdefender missed.

Just avast hangs,I can access taskmanager, but it's very slow.
Whilst scanning avast is using high priority so that is why it is slow opening task manager. You should also see ashServ.exe using a lot of the CPU percentage, so it may just be scanning.

There should be a path displayed of the file/s that are being scanned, if that hangs (or is just slow), could you read it (?) and was it the same file it hung at ?

I assume you sent these trojans to the avast chest ?

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