Does ClamWin quarantine the detected file? If the file is not quarantined, the ClamWin default Infected Files option is to Report Only. Change the default to Move To Quarantine and do another scan to see if it is quarantined. Then upload the file to Virus Total at https://www.virustotal.com/
on the web, which will scan it with 50+ antiviruses, including the Clam AV engine used by ClamWin. See if Clam AV on Virus Total (and other scanners also) detect the file as infected.
If Clam AV is the only scanner on Virus Total to detect it, the detection is a false detection (a "false positive"). If it is a false positive, Virus Total should tell Clam AV about it so they can correct their signature. To speed up the correction, you can upload the file to Clam AV at http://www.clamav.net/reports/fp
on the web.
If Clam AV and several other scanners at Virus Total detect the file as infected, and it was quarantined by ClamWin on your computer, you can either leave the file in quarantine on your computer or delete it.
Thanks for using ClamWin!