To protect a PC from trojans, you can use Avast! Antivirus home edition. When starting this program, the simple user interface help window will automatically display and you can uncheck "Don't show this window next time."
You can change the Avast! Antivirus Settings as you need:
• Click Menu button (see red rectangle in the screenshot above), then click Settings (the menu only displays when the scan is off).
• Change the settings, for example,
- In Common window, uncheck Test Memory During Application Start Up option.
- In Sounds window, check Disable Avast! Sounds option.
Here's how to scan the files:
- Choose what you want to scan. You have three different areas, as follows:
• Local drives/hard disks: Click Local Disk button (see green rectangle in the screenshot above).
• Removable Media: Click Removable Media button, then checkbox the floppies and/or CD/DVD (see pink rectangle in the screenshot above).
• Selected Folder: Click Folder selection button (see red rectangle in the screenshot above), then select the areas to scan, for example, directory C: checkbox (see red rectangle in the screenshot below).
- Select the sensitive level of the next scan (see blue rectangle in the screenshot below), as follows:
• Quick Scan: Scan the possibly dangerous files according to their extension such as EXE, SCR, COM, DOC, etc.
• Standard Scan (default): Scan the possibly dangerous files according to their content.
• Thorough Scan: Scan all files.
• If you want to scan the archive files (such as zipped files), select Scan archive files checkbox (see brown rectangle in the screenshot below).
- If any virus is found (see the screenshot below), you can either Move/Rename, Delete, or Move to Chest (recommended).
• If you choose Delete, then select Delete Files Permanently option. Also, check If necessary, delete file(s) at the next system start option, then click Delete All button (see the screenshot below).
• If you decide not to delete it, you can choose move to chest option. Don’t worry, the virus in the Chest will not be run by accident.
- To delete infected file(s) that have been chosen to move to chest:
• Click Virus Chest button (see yellow rectangle in the screenshot below).
• Click Infected files (see green rectangle in the screenshot below).
• Select file(s) that want to be deleted, then press Delete button.
- Don’t forget to update the virus database regularly by clicking iAvs button (see yellow rectangle in the screenshot).



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