Windows defender on windows 10

[brownknees]

I have an Acer laptop which is rarely used (once or twice a week for an hour).The last two weeks have seen it slow down so I started a quick scan yesterday ,after 12 hours it had only scanned about 50%!Started a full scan this morning but after starting the scan noticed it said quick scan ,so tried a custom scan ...same result ,it is only showing quick scan to all three methods but judging from yesterday it must be a full scan in progress .I will leave it on all day and see how far it gets!!Anybody else had ths problem?

[KhunBENQ]

Just did a quick scan on my 8 year old desktop PC (upgraded to W10).

300 GB harddisk on two partitions.

About half empty,

 

Scan took about 4 minutes.

 

Something is very wrong with your system.

Hardware failure? Software conflict (other antivirus SW?)?

To me it does not make sense to let it run forever.

Shut down, restart.

 

Can you give more details about the laptop.

Disk size, total amount of data.

Can you open task manager and check what processes are running and what percentage of CPU time they use?

Task Manager: right click on task bar and select the corresponding entry.

 

[Chicog]

Check the event logs and see if there are any recurring errors.