Scan taking a long time

[katlomas]

Avast has been carrying out a full system scan of my computer. As of 6:00 a.m. this morning, it has been running for eight and a half hours and has completed 4% of the scan. Is this usual?
Thanks.

[Pondus]

have you changed the default scan settings?

[katlomas]

No, not at all. I've only ever run the program as it was installed.

[Para-Noid]

Try a repair...Control Panel>Uninstall a Program>double click "avast">click "repair">reboot 

[katlomas]

Thank you, Para-Noid. I will try that and let you know if it solves the problem.

[katlomas]

That did the trick, Para-Noid! Thank you for the help. The program completed a full system scan in just over 4 hours.

[mchain]

Must be some bigger drives there.  80 GB + 500 GB drive takes only 29 minutes here for full scan.  More importantly, it is the amount of data scanned rather than the native size of the drive(s).

235 GB data total for both.

PIO issue?

[Randissimo]

The scan duration depends

- on the settings
- which drive(s) are scanned
- how many files are scanned and whether there are rather many small ones like in the Windows folder or big ones
- to some degree on the general computer performance (CPU if you have a really old model or your computer is working poorly in general)
- to some degree on the on the signature database, which is constantly increasing

However, even with maxed settings (max effectiveness, scan whole file, unpack archives) and over 3TB of scanned data (and even without a SSD as a system drive) I've never come past one and a half hour of scanning, except for when I've let it scan with the "ask me what to do when a thread is found"- option and it had triggered some false positives while I've been away from my computer.

The first thing I'd advice the OP to do would be to check the SMART values and general health of the scanned drive with CrystalDiskInfo.

If you want real performance with scanning, get a decent solide-state drive with enough capacity for Windows and all your programs and a normal hard disk drive or an hybrid drive with 7200 rounds per second for storaging purposes although it would be faster, if everything was scanned on a/some SSD(s).

[Para-Noid]

All the OP wanted was help with the scan, not some software they may or may not understand.
Also maybe the OP cannot afford an SSD, I know I can't.
Anyway the OP can now complete their scans. 

[Randissimo]

All the OP wanted was help with the scan, not some software they may or may not understand.

You can easily analyze drives with CrystalDiskInfo, because it highlights critical values and you can check what those mean in Wikipedia.
You don't have to be an expert to understand that a yellow or even red status bar in CDI with a high number of reallocated sectors in the raw values section means that the drive is working poorly and that you should replace it as soon as possible.
If the hard drive is faulty you can optimize as much as you want with clean program/Windows installations, defragmentations, the main problem won't vanish unless you replace the drive and 4h for normal scanning is a major problem unless there are some full 4TB 5400 rpm drives with only a lot of small files in multiple archives while doing some other tasks on the computer.

Also maybe the OP cannot afford an SSD, I know I can't.

You don't need to to replace your HDD with a SSD of equal space which would be insanely costly if you wanted more than 500GB space, however, a small 120 - 128GB SSD with one 1-2TB or your old HDD for storage purposes doesn't cost the world.

[Para-Noid]

Again...the OP wanted scan time help.
Not HDD analysis. Nor did they inquire about getting a SSD.

You have hijacked this thread so it is way off topic. 

[Randissimo]

And again, I've only given a practicable solution. Let's make an easy example: if the tires in your car are becoming flat you don't clean them, you check the air pressure and if it keeps losing air pressure in a short time span, you change the faulty tires.
It's the same with this topic. If there is a hardware related issue, you can't fix it with software. If you can't even understand that much, then I'm simply sorry for you.