Avast antivirus

I recently ran a scan with my Avast anti virus program. Several Threats found came up in the results. There we're options to delete or isolate them. I tried both but nothing happened. How do I get rid of these viruses for good? Thanks. Hal.
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Run a scan of malwarebytes
Malwarebytes

yowanvista said:

Run a scan of malwarebytes
Malwarebytes

+1 ...I use Avast Internet esc.Pro for realtime protection only ..
"never have enough patience to do a FULL scan with avast ...It's darnmm long"
Malwarebyte pro Ver. does a wonderfull job for me .

Boot your computer into Safe Mode (Restart PC then press and hold the 'F8' key until you see the Advanced Boot Options screen, and select Safe Mode with Networking). From there, download and install Malwarebytes Anti-Malware, update first then do a full scan. After the scan, make sure every threat is checked and click on 'Remove Selected'.