Trying to download the initial virus data base and I get this;
ClamAV update process started at Sat Mar 25 13:11:37 2017
WARNING: DNS Resolver: Can't query current.cvd.clamav.net
WARNING: Invalid DNS reply. Falling back to HTTP mode.
Reading CVD header (main.cvd): OK
main.cvd is up to date (version: 57, sigs: 4218790, f-level: 60, builder: amishhammer)
Reading CVD header (daily.cvd): OK
WARNING: getfile: daily-21468.cdiff not found on remote server (IP: 194.8.197.22)
WARNING: getpatch: Can't download daily-21468.cdiff from database.clamav.net
WARNING: getfile: Error while reading database from database.clamav.net (IP: 168.143.19.95): Operation already in progress
WARNING: getpatch: Can't download daily-21468.cdiff from database.clamav.net
WARNING: getfile: Error while reading database from database.clamav.net (IP: 207.57.106.31): Operation already in progress
WARNING: getpatch: Can't download daily-21468.cdiff from database.clamav.net
WARNING: getfile: Error while reading database from database.clamav.net (IP: 168.143.19.95): Operation already in progress
WARNING: Can't download daily.cvd from database.clamav.net
Trying again in 5 secs...
ClamAV update process started at Sat Mar 25 13:12:20 2017
WARNING: DNS Resolver: Can't query current.cvd.clamav.net
WARNING: Invalid DNS reply. Falling back to HTTP mode.
Reading CVD header (main.cvd): Trying host database.clamav.net (128.199.133.36)...
WARNING: Unknown response from remote server
WARNING: Can't read main.cvd header from database.clamav.net (IP: 128.199.133.36)
Trying again in 5 secs...
ClamAV update process started at Sat Mar 25 13:12:43 2017
WARNING: DNS Resolver: Can't query current.cvd.clamav.net
WARNING: Invalid DNS reply. Falling back to HTTP mode.
Reading CVD header (main.cvd): OK
main.cvd is up to date (version: 57, sigs: 4218790, f-level: 60, builder: amishhammer)
Reading CVD header (daily.cvd): OK
WARNING: getfile: daily-21468.cdiff not found on remote server (IP: 194.8.197.22)
WARNING: getpatch: Can't download daily-21468.cdiff from database.clamav.net
WARNING: getfile: daily-21468.cdiff not found on remote server (IP: 64.22.33.90)
WARNING: getpatch: Can't download daily-21468.cdiff from database.clamav.net
Trying host database.clamav.net (128.199.133.36)...
ERROR: getfile: Error while reading database from database.clamav.net (IP: 128.199.133.36): Operation already in progress
Trying host database.clamav.net (69.163.100.14)...

WHAT DID I MANAGE TO SCREW UP?!!?

You probably didn't do anything wrong. The Clam AV mirrors that distribute the Clam AV signatures used by ClamWin are are bit "touchy". I can not usually get updates as soon as I turn on my computer, and sometimes at other times also. I've learned that after the initial download of the signature database(s) upon installation, it's best to just set ClamWin to update signatures hourly starting at the time I usually come online and leave it alone.

If you can't get the initial daily file, try again in an hour or so. I bet it will be updated after a couple of attempts .

Thanks for using ClamWin! Remember that the developers recommend you use it as a backup to a real-time AV because it is an on-demand scanner, not a real-time scanner.

Regards,