Comp,
Check your settings for the resident scanner. Click the avast! icon in the System Tray. Select Standard Shield in the Installed Providers list. Reduce the sensitivity from High to Normal. Alternatively, you can set the sensitivity to Customize and modify the lists of files to scan and under what conditions. Click on the Customize button. Check the extension lists on the Scanner (Advanced) tab. Remove the extensions in the lists of files to scan on opening and/or creating/modifying for any files that you don't wish to be scanned. If you have a lot of archive files on your system, removing their extensions can improve performance. Just remember to manually scan archive files when you open them for the first time if you go this route. If you have directories that contain only safe files, such as text or image files, you can add them to the exclude list on the Advanced tab. Keep in mind that even so-called safe files can have malware hidden in an attached Alternate Data Stream.
If you receive a lot of e-mail, you can disable the Internet Mail or Outlook/Express providers to reduce the impact of scanning while it is being downloaded. The Standard Shield provider will catch viruses in attachments when you attempt to open them or save them. It will also catch one when it is saved to the hard drive if an e-mail tries to download it automatically. The only advantage to using a resident mail scanner is that it prevents viruses from making onto your system in the first place.
Terminate any other providers that you don't need, like P2P. I you don't use these applications, having the provider running consumes memory and causes Windows to rely more heavily on the swap file, reducing performance.
Turn off any features that are redundant with other security features in the applications that you are running. For example, you can disable the Script Blocker if you use Internet Explorer and disable scripting in the Internet Zone. Similarly, you can do this if you are using a firewall that provides this feature. (Outpost has the Active Content Plug-in, which provides script blocking, both globally and on a site-by-site basis.)
Check the help file for more information about these options and the impact changing them will have on your security.
Regards,
Hornus