Always use caution if receiving files from others on IRC channels. Although a percentage of files are safe, sharing of files is the common breeding ground for virus spreading and distribution. Never accept files from people you don't know and never accept files without knowing their full purpose. Files of executable extension such as .BAT, .EXE, .COM, .HLP, .DLL should never be accepted from others as they have the most potential to cause problems or be infected. Scripts should not be accepted from others you do not know.
Automation is another factor in the distribution of viruses and trojans.
Files which support macros should not be accepted, or if they are accepted, make sure to have macro virus protection enabled. If you are unable to verify if macro virus protection is enabled, use alternate viewers such as QuickView or Wordpad as they do not support macros. Office97 applications have viewers available from Microsoft such as Word97 Viewer. Using alternate viewers will minimize the risk of spreading macro virus infections. Use Antivirus software to scan all files received on IRC channels.